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SHIPS' BOATS 

THEIR QUALITIES, CONSTRUCTION, 
EQUIPMENT, AND LAUNCHING 

APPLIANCES 



BY 



ERNEST W. BLOCKSIDGE, M.Inst.N.A, 

MEMBER SOC. N.A« AND M.E. 

SHIP SURVEYOR TO LI.OYl/S REGISTER OK SHII'I'ING, 

FORMERLY SHIP SURVEYOR TO THE MARINE DEPARTMENT OK THE 

BOARD OF TRADE. AND LECTURER ON NAVAL ARCHITECTURE 

TO THE DURHAM HIGHER EDUCATION COMMITTEE 



iVlTH DIAGRAMS AND ILLUSTRATIONS 



LONGMANS, GREEN AND CO. 

39 PATERNOSTER ROW, LONDON 

FOURTH AVENUE & 30th STREET. NEW YORK 
BOMBAY, CALCUTTA, AND MADRAS 

1920 

All rights rrscrftd 



TO THE 

SEAMEN OF THE MERCHANT MARINE 

This treatise is dedicated as a token of unqualified 
admiration of their heroism, self-sacrifice, and 
splendid achievements, which have deservedly gained 
the highest eulogies of the civilised world. These 
pages are a tribute to the memory of those who were 
the victims of a treacherous and barbarous enemy, 
and written with the hope that they will stimulate 
a greater interest in the science and practical 
development of appliances intended to secure the 
full measure of safety for those who voyage 
across the great seas. 



VII 



PllEFACE 

Permission was given the Author, during the period of 
his association with the Marine Department of the Board 
of Trade, to proceed \\dth the publication of this text-book ; but 
in fairness to the officials of. that Department it should be 
stated that they have not had the opportunity to express an 
opinion on the subject-matter previous to publication, owing 
to professional duties taking me to the United States of 
America. 

All matters of controversy have been carefully avoided ; 
the sole purpose in writing the treatise being to circulate 
information with the object of intensifying the interest of its 
readers in the important subject of the ecjuipment of life- 
saving appliances on cargo and passenger vessels. 

Opportunity is now taken to express my personal apprecia- 
tion for the help and encouragement given me by my former 
chiefs, and the Committee of Lloyd's Register, during the 
I)reparation of the work. 

The Author wishes to acknowledge his indebtedness to 
many of the leading -steamship companies, shipbuilders, 
engineers, and boatbuilders, for their valuable and generous 
assistance ; to Mr. W. Mitchell, Ship Surveyor to the Marine 
Department of the Board of Trade, (ilasgow, for his co-opera- 
tion in checking the manuscript ; also to my colleague Mr W. 
Bennett, B Sc, MIN.A., Ship Surveyor to Lloyd's Register of 
Shipping, New York, for reading through the proofs, and for 
many suggestions. 

E. W. BLOCKSIDGE. 

Wilmington, 

North Carolina. 
1919. 



IX 



(From JOHN RUSKIN'S "Hakboxiis op England.") 



Of all things, living or lifeless, upon this strange earth, there 
is but one which, having reached the mid-term of apix)inted 
human endurance on it, I still regard with unmitigated 
amazement. I know, indeed, that all around me is wonderful 
— but I cannot answer it with wonder ; a dark veil, with the 
foolish words, Nature of Things, upon it, casts its deadening 
folds between me and their dazzling strangeness. Flowers 
open, and stars rise, &nd it seems to me they could have done 
no less. . The mystery of distant mountain blue only makes 
me reflect that the earth is of necessity mountainous; the 
sea wave breaks at my feet, and I do not see how it should 
have remained unbroken. 

But one object there is still, which I never pass without 
renewed wonder of childhood, and that is the bow of a boat. 
Not of a racing-wherry, or revenue cutter, or clipper yacht, 
but the blunt head of a common, bluff, undecked sea-boat, 
lying aside in its furrow of beach sand. The sum of Navi^^a- 
tion is in that. You may magnify it or decorate as you will, 
you do not add to the wonder of it. Lengthen it with complex 
tracery of ribs of oak— carve it and gild it till a column of 
light moves beneath it on the sea — you have made no more 
of it than it was at first. That rude simplicity of bent plank, 
that can breast its way through the death that is in the deep 
sea, has in it the soul of shipping. Beyond this, we may 
have more work, more men, more money, we cannot have 
more miracle. 

For there is first, an infinite strangeness in the perfection 
of the thing, as work of human hands. I know nothing else 
that man does, which is perfect, but that : all his other doings 



xl 



XII 



have some sign of weakness, aflfectfction or ignorance in them. 
They are over-finished or under-finished; they do not quite 
answer their end, or they show a mean vanity in answering it 
too well. 

But the boat's bow is naively perfect; complete without 
an effort. The man who made it knew not that he was 
making anything beautiful, as he bent its planks into those 
mysterious, ever-changing curves. It grows under his hand 
into the image of a sea-shell; the seal, as it were, of the 
flowing of the great tides and streams of ocean stamped on 
its delicate rounding. He leaves it when all is done, without 
a boast. It is simple work, but it will keep out water, and 
every plank thenceforward is a Fate, and has men's lives 
wreathed in the knots of it,' as the cloth -yard shaft had their 
deaths in its plumes. 



CONTENTS . 

PAET I 

SCCriOK l>AOR 

Introductory 1 

PAKT II 

A. Trades of vessels as affecting boat accommodation and the installa- 
tion of davits 4 

B Classification of boats 20 

C. Form, stability, strength, and capacity of boats ...... 28 

PART III 

A. Timber — conversion, seasoning, diseases, selection, strength, etc. . 84 

B. Principal woods used in the construction of boats, and their 

respective qualities 97 

C. Tlie equipment of a boat-yard 1()5 

PART IV 

A. Construction of Class Ia open lifeboats 110 

B. Construction of Class Ib open lifeboats 195 

C. Construction of Class III. boats .... 199 

D. Construction of Class IIa open lifeboats with collapsible bulwarks . 2(\0 

E. Construction of Class Ic, IIb, and lie pontoon lifeboats with 

collapsible bulwarks 223 

PART V 

A. Motor boats 235 

B. Nested boats 2GG 

C. Surf boats 273 

D. Steel boats 278 

PART VI 

A. Details of lifting hooks, keel plates, chain slings, etc 2S9 

B. Boats* engaging and disengaging gear 311 

C. Construction of buoyancy air-cases 330 

xili 



xiv CONTENTS 

PART VII 

BKCTION J'AOK 

A. Equipment of boats 342 

B. Sftils 357 

C. Methods of galvanising 377 

D. Painting 882 

K. licpairs and maintenance of boats 380 

PART VIII 

Fire and boat drills 391 

PART IX 

Weights of lifeboats, equipment, and materials 399 

PART X 

A. Boat stowage and transporting arrangements 403 

B. Roimd bar radial davits 421 

C. Patent appliances for launching ships* boats 444 



APPENDIX 

A. Instructions for the construction of life-rafts 469 

B. Instructions for the construction of buoyant apparatus .... 473 

C. Syllabus for technical instruction in boatbuilding 479 

D. Table of squares and cubes 482 

E. Decimals of a foot for each ^^ of an inch .... 488 

P. Decimals of an inch for each ,}-^ of an inch 490 

G. Approximate freeboard for Class I. open boats 490 

Index 491 



TABLES 

PART II.— SECTION A 

KClCRKn PAOK 

I. Minimum number of set« of davits and open boats for vessels 
in Class I. Poreign-going, or Classes I. and V. Home Trade, 
and minimum lifeboat capacity 10 

II. Minimum lifeboat capacity for vessels in Class I. or Class V. 

Home Trade 14 

m. Minimum number of sets of davits for vessels in Class V. 

Home Trade, in certain cases IG 

IV. Minimum lifeboat capacity for vessels in Class V. Home 

Trade, in certain cases 16 

V. Minimum number of sets of davits for vessels in Classes VI. 

and VII. Home Trade 17 

PART II.— SECTION 

VI. Minimum breadths to inside of planking at half-midsbip depth 

for open boats, Classes I. and III 35 

VII. Dimensions of open lifeboats, Class I., and boat.'? Clans III., 

above 125 cubic feet capacity .38 

VIII. Dimensions of open lifeboats, Class I., and boats Class TIT., 

below 126 cubic feet capacity ... 30 

IX. Dimensions of open lifeboats, Class Ha, and pontoon life- 
boats. Classes IIb and He 40 

X. Decimal measurement conversion table 40 

XI. Comparison between boats of various Classes, with full load 62 
XII. Particulars of boats A and C under stability tests (Report of 

committee on boats and davits) 03 

PART III -SECTION A 

XIII. Strength and elasticity of timber 90 

PART IV.- SECTION A 

XrV. Scantlings for wooden lifeboats, Classes Ia and Ib, and boats 

of Class III Ill 

XV 



xvi TABLES 

NUMBER PAGE 

XV. Minimum number of strakos of planking in clinker-built 

boats 6t Classes Ia, Ib, and III 132 

XVI. Particulars of copper nails and roovcs 148 

XVII. Approximate number of copper fastenings in a 26-ft. lifeboat, 

Class Ia 149 

XVIII. Dimensions of thwart knees, etc., in open boats of Classes I. 

and III ' .... 170 

PART VI.— SECTION A 

XIX. Scale of sizes for lifting books and keel plates for open l)oat8 

of Classes I. and HI 29C 

XX. Scale of sizes for keel plates of Type C for boats 20 feet in 

length and under 301 

XXI. Scale of sizes for keel plates, when open boats of Classes I. 

and III. are lifted near the ends 803 

PART VII.— SECTION A 

XXII. Particulars of thwarts, crutches, and oars, for open boats of 

Classes I. and III 347 

XXIII. Distance between bottom of thwart and top of keelson in 
open boats of Classes I. and III. for the accommodation 
of biscuit cases 353 

• 

PART VII.— SECTION B 

XXIV. Sail areas of open boats 366 

XXV. Length and sizes of masts for open boats of Classes I. and III. 376 

PART IX 

XXVI. Weight of details of boats* equipment 399 

XXVII. Details of weights of lifeboats (Classes Ia and Lb) . . . . 400 

XXVIII. Weights of materials 401 

XXIX. Weights of persons 402 

PART X. -SECTION B 

XXX. Approximate weight and strength of iiianiln rope .... 430 

XXXI. Approximate weight and strength of tibre-clad hoisting rope 432 

XXXIl. Equivalent sizes for hollow and Rulid iron davits .... 441 



SHIPS' BOATS 



PART I 

INTRODUCTORY 

Many valuable books dealing with the design and construction 
of ships have been written at periodical intervals by eminent 
Naval Architects, and become standard works of reference in the 
libraries of our Technical Societies and Institutions. Many 
questions associated with the theoretical and practical aspects 
of the subject have been thoroughly investigated and published 
for the benefit of students desiring to extend their knowledge in 
the Science. The sources of information are therefore numerous 
and varied. 

It is a matter of some surprise that the important subject 
of the equipment of cargo and passenger vessels with life-saving 
appliances has never been dealt with in detail and presented as 
a technical volume for the guidance of those " that go down to 
the sea in ships, that do business in great waters." 

Information hitherto has, to some extent, remained sealed, 
not from any desire to hinder the circulation of knowledge, but 
due mainly to the fact that such technical literature must 
necessarily be written during the leisure hours of a practical 
man, after the labours of the day, when physically and mentally 
he is not at his best. 

The attention of the whole world was directed to the terrible 
disasters which befell the large passenger steamers TiUinic, 
Empress of Ireland, Falaba, Lusiixinia, and hundreds of other 
vessels sunk at sight by the unconstitutional methods of an 
arrogant enemy, during the recent war. 

The subject of providing the best apparatus for securing the 
greatest measure of safety for passengers and crew, has created 
widespread interest and demanded the close attention of the 
governing authorities. 

B 



2 SHIPS' B0AT8 

In spite of many difficulties, tlie writer has been prompted 
to bring together in concrete form the reaulta of some measure 
of practical experience a8sociat«d with the methods of equipping 
merchant vessels with life-saving appliances. 

The present volume is mainly devoted to the subject of Boats ; 
their construction, stowage, equipment, and launching appliances. 
It has been found impossible to make any detailed reference to 
the subject of life-rafts and buoyant apparatus, but the general 
instructions relating to these portions of the life-saving equipment 
have been inserted in the Appendix. 

No pretence has been made to deal with abstruse calculations, 
and the author has endeavoured to confine himself to everyday 
language in explaining the various methods of construction 
operating in the boat yards and engineering works. 

A feature of the present edition is the large number of illustra- 
tions, which it is anticipated will prove of some assistance to 
Shipbuilders and Ships' Officers, wlio have little opportunity to 
secure the complete information in suitable form for reference. 

It is not considered out of place to give a brief summary of 
the progress of legislation which insists on certain requirements 
being carried out on all merchant vessels for the safety of 
passengers and crew. 

Previous to the year 1890, the boat accommodation for all 
British ships and foreign ships canying passengers between places 
in the United Kingdom, was governed by Clause 292 of the 
Merchant Shipping Act of 1854, and based on the veaael's register- 
tonnage. The limit for a vessel of 1000 tons and upwards was 
seven boats, provided one was a lifeboat, in the case of a 
passenger vessel. Provision was not made for additional life- 
saving appliances beyond the supply of a number of lifebuoys. 

In March. 1886, a Departmental Committee was appointed 
by the Board of Trade to inquire into the question of boats, 
rafts, and life-saving apparatus carried by eea-going merchant 
vesseb, and when considering the equipment of passenger steam 
vessels carrying large numbers of emigrants across the Atlantic, 
it was recommended that the provision under the statutory 
requirements was inadequate and that each ship should have 
sufficient life-saving apparatus for all persons on board. 

As a result of the recommendations of a Select Committee of 
the House of Commons, presided over by Lord Charles Beresford, 
in the year 1887, Rules for Life-saving Apphances came into 
operation on the 31st March, 1890, which adopted the principle 
that on all Foreign and Home Trade cargo vessels, the boat 



INTRODUCTORY 3 

accommodation should be sufficient for all on board, and that 
on steamships engaged in such trades, this accommodation should 
be provided in boats under davits on each side of the vessel. 
These rules substituted gross for register tonnage as the basis of 
scale for the equipment of emigrant and passenger ships up to 
9000 tons and upwards ; which limit was again increased in 
1894 to 10,000 tons and upwards. This substitution was the 
means of increasing the boat accommodation in steamships by 
about 50 per cent. Provision was also made for life-belts and 
other buoyant apparatus to be carried for all persons on board. 

Further rules and regulations relating to life-saving appliances 
were introduced at various periods between the years 1902 
and 1914, to provide for the adequate equipment of vessels 
which were constantly increasing in size and passenger accommo- 
dation. 

After the regrettable loss of the s.s. Titanic in the Atlantic 
Ocean, a Merchant Shipping Advisory Committee was appointed, 
followed by a Departmental Committee on Boats and Davits, 
and the International Conference for the Safety of Life at Sea. 

The British authorities have always recognised the importance 
of safeguarding both passengers and crew, as the before-mentioned 
investigations will testify. 

The Rules for Life-saving AppUances, issued in 1914, are those 
which now govern the equipment of vessels. Boat accommo- 
dation and the number of davits to be provided depend, not on a 
tonnage scale, but on the registered length of the vessel. 

No doubt certain modifications and additions will be made 
in the future as a result of the experience gained during the recent 
war, but the standard of the present requirements are of a very 
high class. 

The foreword given in this text-book is a very beautiful and 
decorative expression of an author's view of the lines and form 
of an ordinary open boat. The practical man sometimes finds, 
when boats are constructed under certain conditions, that beauty 
of form is not always a guarantee that " it will keep out water." 
Experience has proved the necessity for regulating the con- 
struction of ships' boats by a very high standard of workmanship, 
and the builders are now guided by a complete and com- 
prehensive specification. 

If the circulation of this text-book is the means of increasing 
the interest in the subject of the equipment of our merchant 
fleet with satisfactory life-saving appliances, the author will be 
gratified with the result. 



PART II 

SECTION A.— TRADES OF VESSELS AS AFFECTING 
BOAT ACCOMMODATION AND THE INSTALLATION 
OF DAVITS 

The life-saving equipment of our Merchant Fleet is governed by 
the nature of the service for which the vessels are intended. 

The requirements of Clause 427 of the British Merchant 
Shipping Act of 1894 empower the Board of Trade to draw up 
regulations for the installation of life-saving appliances on vessels, 
which will ensure a large measure of safety at sea for the passengers 
and crew. 

From time to time the Marine Department of the Board of 
Trade have sought the advice, experience, and co-operation of 
influential Committees before bringing into operation their 
Regulations. 

The recommendations of the Departmental Committee on 
Boats and Davits, and the results of the investigations made 
by the International Conference on Safety of Life at Sea, have 
now been embodied in the latest rules. 

For the purpose of drawing up Rules for Life-saving Appliances 
the vessels have been classified under two headings, viz. — 
(1) Foreign-going, and (2) Honie Trade. Each of these classes 
has been sub-divided so as to include and separately identify the 
various vessels, to enable the equipment to suit the particular 
type of ship or trade in which the vessel is engaged. 

There are three important sections of the Rules for Life-saving 
Appliances which exercise a controlling influence on the question 
of equipping a vessel with the regulation number of boats and 
sets of davits, viz. General Rules Nos. 2, 10 and 20. 

Portions of these rules which affect all new vessels now under 
construction are, therefore, given in detail, to enable the reader 
to familiarise himself with the modifications which may become 
necessary owing to the special features of the ship's design. 



TRADES OF VESSELS AND BOAT ACCOMMODATION 5 

These modifications are pemussible under certain conditions, 
which are indicated in the rules and are as follows : — 



GENERAL RULE 2 OF THE RULES FOR LIFE- 
SAVING APPLIANCES. 

Power of the Board of Trade lo accept alternatives. 

" The Board of Trade shall have power, in general or in any 
' particular case, to accept any boat, raft, buoyant apparatus, 
' or other life-saving appliance, in lieu of a life-saving appUance 
' required by these rules, subject to such conditions as they 

* may impose, if they are satisfied that under those conditions 
' it will be as effective as the appUance required by these rules. 

" Provided that in the case of a foreign-going passenger 
' steamer no life-saving appUance shall be accepted in Ueu of a 

* lifeboat required by these rules, except either some other 
' approved type of lifeboat or a life-raft approved as being 
' in every respect as efficient as the pontoon life-raft described 
' in General Rule 10. 

" Provided also that no life-raft shall be accepted on a foreign- 

* going passenger steamer unless the total cubic capacity of the 
' lifeboats provided is at least equal to the greater of the two 
' foUowing amounts :— 

" (i.) 75 per cent, of the total capacity required to 
" accommodate all the persons carried. 
" or (u.) The minimum capacity required by Column C of 
" the Table in Appendix I." (See p. 10.) 



GENERAL RULE 10 OF THE RULES FOR 
LIFE-SAVING APPLIANCES. 

Life-rafts, 

** (1) An approved pontoon life-raft shall satisfy the foUowing 
'* conditions : — 

(i.) It shall be reversible and fitted with bulwarks of 

" wood, canvas, or other suitable material on 

both sides. These bulwarks may be 

collapsible. 

(ii.) It shall be of such size, strength, and weight 

" that it can be handled without mechanical 






SHIPS' BOATS 



" appliances, and, if necessary, be thrown from 
" the vessel's deck. 






(iii.) It shall have not less than three cubic feet of 
air-cases or equivalent buoyancy for each 
person whom it can accommodate, 
(iv.) It shall have a deck area of not less than four 
square feet for each person whom it can 
*' accommodate and the platform shall be not 
" less than six inches above the water level 
" when the raft is loaded. 
** (v.) The air-cases or equivalent buoyancy should be 
" placed as near as possible to the sides of the 
" raft. 
" (2) Every raft shall be marked to the satisfaction of the 
" Board of Trade in such a way as plainly to indicate the number 
" of persons for which it is approved. 

** (3) Two children under the age of twelve may be carried in 
place of one adult person. 

(4) In ships which carry rafts there shall be a sufficient 
number of rope ladders, or other approved appliances, always 
available for use in embarking the persons in the rafts." 






PART OF GENERAL RULE 20 OF THE RULES FOR 

LIFE-SAVING APPLIANCES. 

Exemptions. 

" (1) If it appears to the Board of Trade, on the application 
" of the owner of any ship, that it is not practicable or reasonable 
" to fit in that ship the number of sets of davits required by these 
" rules, the Board may direct that one or more sets of davits 
" may be dispensed with in that ship subject to such conditions, 
" if any, as the Board may require. 

" Provided that, in the case of a foreign-going passenger 
'' steamer, the number of davits fitted shall not be less than the 
** minimum number of open boats of Class I. required by these 
" rules, except in the following case : — 

" If a large proportion of the persons on board are accommo- 
'' dated in boate whose length is greater than 50 feet, a further 
'' reduction in the number of sets of davits may be allowed if the 
'* Board of Trade are satisfied that the arrangements are in all 
*' respects satisfactory. . . . 



it 






TRADES OF VESSELS AND BOAT ACCOMMODATION 7 

" Provided further that, in the case of a foreign-going 
' passenger steamer, the owner of the ship in question shall be 
' required to prove, by a test made in the presence of a Board 
' of Trade Surveyor, that all the boats can be launched in a 
' time, to be fixed by the Board of Trade. The conditions of 
' this test shall be as follows : — 

" (i.) The ship is to be upright and in smooth water. 
" (ii.) The time is the time required from the beginning 
of the removal of the boat covers, or any 
other operation necessary to prepare the 
" boats for lowering, until the last boat, or 
" pontoon raft, is afloat. 
" (iii.) The number of men employed in the whole opera- 
" tion must not exceed the total number of 
" boat hands Ijhat will be carried on the 
" vessel imder normal service conditions, 
(iv.) Each boat when being lowered must have on 
board at least two men, and its fuU equipment 
as required by these rules." 
In discussing the various regulations which control the number 
of boats and sets of davits to be installed on ships, each type of 
vessel will be dealt with in the order of classification and under 
the two headings of '* Foreign-going," and " Home Trade." 

FOREIGN-GOING. 

Class I. — Foreign-^oing passenger steamers, includitig 

emigrarU ships. 

The registered length of passenger steamers governs the 
number of sets of davits to be installed, and in combination with 
these davits, a minimum aggregate cubic capacity for the lifeboats 
must be obtained. 

Lifeboats must be carried in such numbers as will be 
sufficient to accommodate the total number of persons on board, 
or the number which the ship is certified to carry, whichever is 
the greater. 

The nimiber of sets of davits to be fitted to a ship of this 
class must be in accordance with Column A of Table I., p. 10. 

Each set of davits must have a lifeboat of Class I. attached 
to it ; and of these lifeboats, at least the minimum specified in 
Column B of Table I. must be open boats. 

The aggregate cubic capacity of the lifeboats in feet must not 
be less than the minimum specified in Column C of Table I. 



SHIPS' BOATS 

An example will be taken to explain liow tlieae various clause» 
operate in a particular vessel, and the permissible deviations 
which may be made with the sanction of the Board of Trade, 
under specified conditions, to suit the design of vessel and the 
number of passeugei-s carried. 

Consider a foreign-goiiiy passenger steamer 500 feet in 
lengtli. 

The minimum number of scte of davits required to be fitted 
in accordance with Table I. is 14^ and the minimum number of 
open boats of Class I. which must be attached to these davits b 
10. This leaver four boats to be attached to the remaining 
davits, which may be either open boat« or pontoon boat« of 
Class I. ; that is to say, all boats attached to davits must have 
rigid sides aud not collapsible bulwarks. 

The minimum aggregate capacity of tlie lifeboats taken from 
Column C of Table I. must be 17,310 cubic feet. 

The maximum size of a Class 1a lifeboat for the vessel taken 
as an example would be 28'0'x8'5' x3'5', giving a capacity of 
500 cubic feet and accommodation for 50 persons. 

Dividing tlie minimiun aggregate by the single boat capacity, 

i.e. - J^.-, we find that 34 boats are required. 
oOO ^ 

Fourteen lifeboats of Class I. are already provided and attached 
to davits. Fourteen boats with collapsible bulwarks could be 
stowed beneath the Class 1. boats, leaving six others of Class I. 
or Class II. to be stowed inboard. 

The provision of 34 boal*i of the stated size would give accom- 
modation for about 1700 passengers. 

For the purpose of explaining the Lile-saving Appliances 
Rules, let us suppose the shipowner wishes t<) carry a larger 
number of passengers, say 2000. Then it woidd be necessary to 
provide additional lifeboats to accommodate the full number of 
persons. 

If the shipowner wishes to claim the provisions contained in 
General Rule 2 of the L.S.A. Rules, we find that seventy-five 
per cent, of the boat capacity to accommodat-e 2000 passengers, 
is 15,000 cubic feet. The minimum capacity required bv 
Column C in Table I. is 17,310. The Board of Trade may, there- 
fore, consider, in this case, the question of the supply of approved 
life-rafts in lieu of the lifeboats required by the rules, to make 
up for the additional number of passengers carried. 

j\gain. suppnsc the vessel was only carrying WKI passi^ngera 
und crow, then it would only be necessary to provide ten davibi 



TRADES OF VESSELS AND BOAT ACCOMMODATION 9 

instead of fourteen, when treated in accordance with the registered 
length. 

If the shipowner or shipbuilder considers that it is not 
practicable or reasonable to fit the number of sets of davits 
required by the rules, then special application must be made to 
the Board of Trade for permission to dispense with one or two 
sets. The conditions imder which approval is granted are stated 
in General Rule 20 of the L.S.A. Rules, the details of which have 
already been given and are self-explanatory. 

All the davits of passenger vessels must be of such a design 
that they can laimch the boat from its stowing position and 
lower it safely into the water, the ship being assmned to have 
a list of 15 degrees. 

If the master or owner of a ship of this class claims to be 
carrying on a voyage, fewer lifeboats and life-rafts than will pro- 
vide suflScient accommodation for all persons for which the ship 
is certified, he must declare before the collector or other officer 
of the Customs, before the time of clearance, that the lifeboats 
and life-rafts actuallv carried, will be sufficient to accommodate 
all persons who will be carried at any time during the voyage to 
foreign ports and the voyage back to the United Kingdom. 

Provision is also made in the Life-saving Appliances Rules 
by the Board of Trade for passenger steamers which call at 
certain foreign ports during the voyage from or to the United 
Kingdom to take on board at these places an additional number 
of passengers, within the terms of the ship's passenger certificate. 
The extra boats, davits, or other life-saving equipment for the 
additional passengers may comply with the rules applicable to 
the class of Home Trade voyage to which the voyage has been 
scheduled as similar. 

This clause operates in quite a large number of vessels which 
leave the United Kingdom witli passengers for various ports of 
call on the voyage to China, and in running along the Chinese 
coast a large number of emigrants are carried between the different 
sections. 

The two following notes are of importance : — 

Note I, — All open lifeboats carried on a foreign-going passenger 
steamer must be fitted with buovancv air-cases. 

Note II. — In arranging the boat accommodation for foreign- 
going vessels which are certified to carry not more than twelve 
passengers, reference should be made to Section C of Part 1 V. in 
regard to the provision made for the inclusion of Class HI. Boats 
in the statutory equipment. 



10 



SfflPS' BOATS 



TABLE I. 

Appendix /. of Ruhsfor Life-saving Appliances, 1914. 

MiKiMUBC Number of Sets of Davits and the Minimum Number of Open 
Boats required to be provided in a Steamship in Class I., Foreign- 
QOiNO, or in Class I., Home Trade, or in Class V., Home Trade (except 
in certain cases), and the Minimum Lifeboat Capacity for the 
purposes of General Rule 2. 









(A.) 


Registered Length of the Ship. 


Minimum 
number of sets 




of davits. 


Feet. Feet. 




100 and under 120 . . . 


2 


120 „ 140 . 






2 


140 ,. 160 . 






2 


160 „ 175 . 






3 


175 ., 100 . 






3 


190 .. 205 . 






4 


205 „ 220 . 






4 


220 ., 230 . 






5 


230 „ 245 . 








245 „ 255 . 






6 


255 „ 270 . 






6 


270 ,. 285 . 






7 


285 „ 300 . 






7 


300 „ 315 . 






8 


315 „ 330 . 






8 


330 „ 350 . 






9 


360 „ 370 . 






9 


370 ., 390 . 






10 


390 „ 410 . 






10 


410 „ 435 . 






12 


435 „ 460 . 




i 12 


460 „ 490 . . 




i 14 


490 „ 520 . . 




14 


520 „ 550 . . 




16 


550 „ 580 . . 




16 


580 ., 610 . . 




18 


610 „ 640 . . 




18 


640 „ 670 . . 




20 


670 , 700 . . 




20 


700 „ 730 . . 




22 


730 ,. 760 . . 






22 


760 „ 790 . . 






24 


790 ., 820 . . 






24 


820 ,. 855 . . 






26 


856 „ 890 . . 






26 


890 „ 925 . . 






28 


92& ., 960 . . 






28 


960 .. 995 . . 




30 


995 „ 1030 . . 






30 



(B.) (C.) 

Minimum Minimum aggre- 

number of open gate cubic capacity 

boats, Class I. of lifeboats in feet. 



2 


980 


2 


1,220 


2 


1,550 


3 


1,880 


3 


2,390 


4 


2.740 


4 


3,330 


4 i 


3.900 


4 


4,660 


5 


5.100 


5 


5,640 


5 1 


6.190 


5 


6,930 


6 


7,560 


6 .: 


8,290 


7 


9,000 


7 


9,630 


7' 


10,660 


7 


11,700 


9 


13,060 


9 


14,430 


10 


16,920 


10 


17,310 


12 


18,720 


12 


20,360 


13 


21,900 


13 


23,700 


14 


26,350 


14 


27,050 


15 


28,560 


15 


30,180 


17 


32,100 


17 


34,350 


18 


36,460 


18 


38,760 


19 


41,000 


19 


43,880 


20 


46,360 


20 


48,760 



\Mien the length of the ship exceeds 1,030 feet the Board of Trade shall 
prescriba the minimum number of sets of davits and the minimum number of 
open boats. 



TRADES OF VESSELS AND BOAT ACCOMMODATION 11 

Class II. — Foreign-going steamships not certified to carry 
passengers : — 

Boat accommodation must be provided on each side 
of the vessel for the total number of persons carried on 
board. 

The inclusion of boats without buoyancy air - cases 
in the statutory equipment, is permissible in this class of 
vessel. 

If the total number of lifeboats required exceeds two, a boat 
of Class III. may be carried in lieu of one of them ; and if the 
number exceeds three, one or two boats of Class III. may be 
carried in lieu of the same number of lifeboats. 

Every boat which forms part of the statutory equipment of a 
vessel must be attached to davits. 

Supposing a cargo vessel of this class carries a crew of 53, in- 
cluding the master, then one lifeboat of Class I a, 240' X 7*5' X 30' 
with seating accommodation for 32 persons, and one boat of 
Class III. 200'x6"75'x2*6', accommodating 21 persons, stowed 
on each side of the vessel and attached to davits, would be a con- 
venient arrangement and comply with the regulations. There 
would therefore be boat accommodation for 106 persons, under 
four davits ; and for this reason the Rules for Life-saving Ap- 
pliances do not insist on davits being fitted with mechanical 
arrangements for launching the boats against a list. 

There is an element of doubt in the minds of some ship- 
builders and boatbuilders as to whether the Class III. boats carried 
on a cargo steamer are required to be equipped with the 
details of outfit in the same manner as the Class I. lifeboats. 
The whole of the boats carried on a vessel of this class, if they 
appear on the Life-saving Certificate issued by the Board of 
Trade Surveyor, must be constructed and equipped alike in 
every particular, whether they are Class I. or Class III. with 
the exception that Class III. boats are not fitted with buoyancy 
tanks. 

The United States Steamboat Inspection Service previous to 
June, 1919, required boat accommodation for the total number of 
persons carri^ on board, cargo and passenger steamers being 
alike in this respect, but since that date instructions have been 
issued that in the case of ocean-going cargo steamers suflicient 
boat accommodation must be provided for all persons on board, 
on each side of the ship, thus coming into line with the 
requirements which operate in Great Britain. 



12 SHIPS' BOATS 

Class III. — Foreign-gaing sailing ships carrying more than 
twelve passengers : — 

A vessel of this class must carry lifeboats in such number 
and aggregate capacity as shall be sufficient to accommodate all 
persons on board. 

All the lifeboats must be attached to davits so far as practi- 
cable in the opinion of the Board of Trade Surveyor. 

The position of the davits is dependent on the arrangements 
made for working the sails. 

Turning-out gear or mechanical davits are not considered 
essential for vessels of this class. A very small number of these 
vessels are now in actual service. 

Class IV. — Foreign-going sailing ships not carrying more than 
ttvelve passengers : — 

A ship of this class carries a lifeboat or lifeboats of Class I., 
and of such capacity as will be sufficient to accommodate all 
the persons on board. 

If only one lifeboat is required, an additional boat of 
Class III. must also be carried ; and if the total number of 
boats required exceeds two, then a boat of Class III. can be 
carried in lieu of one of the lifeboats. 

Two boats at least must be attached to davits, one on each 
side of the ship. 

The provision to carry boats for the full number of persons on 
board, on each side of the ship, which appUes to cargo steamers, 
does not operate in the case of saiUng vessels. 



HOME TRADE. 

British Hofne Trade Limits. — Between places in the British 
Isles (the United Kingdom, Channel Isles, and the Isle of Man), 
or between the British Isles and the Continent of Europe, between 
the River Elbe and Brest inclusive. 

Class l.~Steamships certified to carry passengers anywhere 
within Home Trade limits : — 

In vessels of this class, the registered length comes into 
operation and the number of sets of davits is governed by 



TRADES OF VESSELS AND BOAT ACCOMMODATION 13 

Ck>lamn A of Table I., as in the case of foreign-going passenger 
vessels. 

Each set of davits must have a lifeboat attached 
to it. 

The lifeboats attached to the davits may be either open or 
pontoon lifeboats, but no ship shall cany, attached to davits, 
a number of open lifeboats less than that specified, in accordance 
with its- length, in Column B of Table I., p. 10. 

If the specified number of lifeboats is suflScient to accom- 
modate the whole of the passengers and crew on board, it is 
unnecessary to provide a number of sets of davits greater than 
the number of boats. 

If the lifeboats attached to davits do not provide suflScient 
accommodation for the total number of persons carried, or which 
the vessel is certified to carry, whichever number is the greater, 
then additional lifeboats must be carried in order to make up 
the total capacity as specified in Table II., p. 14. 

If the lifeboats carried in accordance with the regulations are 
insuflSicient to provide accommodation for the total number of 
persons which the ship is allowed by her ordinary passenger 
certificate to carry, approved life-rafts, approved buoyant deck 
seats, or other approv^ buoyant apparatus must be carried, so 
that these additional life-saving appliances, together with the 
specified number of lifeboats, provide sufficient accommodation 
for the total number of persons which can be legitimately carried 
on board. 

Many vessels of this class Are given a special certificate when 
conveying a large number of passengers during the summer, on 
daylight voyages between the 20th March and the 30th September, 
inclusive. To make adequate provision for the additional number 
of persons carried beyond the number allowed by her ordinary 
passenger certificate, the lifeboats, approved life-rafts, approved 
buoyant deck seats, or other approved buoyant apparatus carried 
on board, must provide sufficient accommodation for 80 per cent. 
of the number allowed by the special passenger steamer's certifi- 
cate, but in no case must the total accommodation provided by 
the life-saving appliances be less than that which is sufficient for 
the number of persons allowed by the ordinary passenger 
certificate. 



14 



SHIPS' BOATS 



TABLE IL 

Appendix IL of Rules for Life-saving Appliances (1914). 

Minimum AaoBEGiiTE Cubic Capacity op Lifeboats to be carried in a Ship 
IN Class I., Home Trade, launched on or after the 1st March, 1913, 
OR IN Class V., Home Trade, launched after that date (except in 
certain cases). 



Length of vesael in feet. 



Minimum aggregate capacity 
of lifebofits, in cubic feet. 









100 and under 120 
120 „ 140 
)40 „ 160 


160 
176 
190 


It 
«» 

11 


175 
190 
205 


205 
220 
245 


»» 
»» 


220 

245 

•270 


270 
300 




300 
330 


330 


tf 


370 


370 
410 




410 
460 



400 
600 
850 

1150 
1300 
1450 

1600 
1850 
2350 

3000 
3750 

4400 

5100 
6000 



In the case of a vessel of under 100 feet, or over 460 feet, the cubic capacity 
of the lifeboats to be carried shall be prescribed by the Board of Trade. 



Class IL — Steamships trading within Home Trade limits, hut 
ryot certified to carry passengers : — 

Vessels of this class when 100 feet in length and over, must 
carry a boat or boats on each side of the ship of such capacity as 
shall be sufficient to accommodate all persons on board. One 
of the boats may be of Class III., but the remainder must be of 
Class I. 

All the boats must be attached to davits. 
^ Vessels under 100 feet in length must carry one lifeboat of 
Class I. of sufficient capacity to accommodate all persons on 
board, and stowed in such a manner that it can be readily launched 
on either side of the ship. It is, therefore, not compulsory to 
fit davits in these vessels, and the usual procedure is to utilize 
the derrick from the* main mast as shown in Fig. 237. 



TRADES OF VESSELS AND BOAT ACCOMMODATION 15 

Class IIL — Sailing ships carrying passengers anywhere within 
Home Trade limits : — 

A ship of this class must be provided vrith a lifeboat or life- 
boats of such capacity as will be sufficient to accommodate the 
total number of persons on board. 

The boats are attached to davits as far as practicable. 

In sailing vessels there is always the difficulty of the davits 
interfering with the proper working of the sails, and each case 
must therefore be dealt with when considering the particular 
rigging arrangements fitted to the vessel. 

Class IV. — Sailing vessels trading within Home Trade limits, hit 
not carrying passengers : — 

Provision must be made for a boat or boats of such capacity 
as will be sufficient to accommodate all persons on board. At 
least one of the boats must be an open boat of Class I. The 
boats are stowed so that they can readily be placed in the water 
on either side of the ship. It is not always possible to attach the 
boats to the davits owing to the restricted space for working the 
sails. 

A concession is made in the case of a vessel of this class if 
under 100 feet in length ; the boat or boats carried may be of 
Class III. 

Class V. — Steamships certified to carry passengers on short 
specified passages along the coasts of the United Kingdom^ or between 
Great Britain and Ireland, or between Great Britain or Ireland and 
the Isle of Man. 

The same regulations which govern the boat accommodation 
and davit equipment of vessels of Class I. of the Home Trade, also 
operate in the case of vessels of Class V. and in addition a special 
provision is made when— 

(a) A ship of this class is engaged near the coasts of the 
United Kingdom, specially scheduled by the Board of Trade for 
this purpose, or — 

(6) When engaged on dayUght excursions, specially scheduled 
by the Board of Trade for this purpose, between the 1st June and 
the 31st August, inclusive. 

In each of these cases the vessels are not required to carry 
more sets of davits, or lifeboats of a greater aggregate cubic 
capacity, than are respectively specified in the second columns of 
Tables III. and'lV. on p. 16. 



16 



SmPS' BOATS 



TABLE III. 

Appendix III. of Rules for Life-saving Appliances (1914). 

Minimum Number of Sets of Davits required to be provided in a Steam* 

SHIP in Class V., Home Trade, in certain cases. 



Length of steami^hlp in feet. 


1 Bf inimura number of sots of 
1 (lavita. 

1 


Under 180 




2 


180 and under 210 . . . 


3 


210 


240 ... 


4 


240 „ 


270 ... 


T) 


270 


300 .. . 


(> 


300 


330 ... 


7 


330 


3(K) . . . . 


8 



In the caac of a stoamBhip of over 360 feet, the number of sets of davits to 
be provided shall be prescribed by the Board of Trade. 

TABLE IV. 

Minimum Aggregate Cubic Capacity of Lifeboats to be carried in a 
Steamship in C^ass V., Home Trade, launched on or after the 1st 
March, 1913, in certain cases. 



T^nffth nf atfliinmhin in f^flt ' Minimum aggregate capacity 
Lengtn or steamship in feet. ^^ lifeboats in cubic feet. 


100 and under 120 . 


. . . , 300 


120 ., 140 








4<M) 


140 „ im 








500 


UA) „ 180 








<J00 

1 


ISO ., 195 








700 


195 „ 210 








8(H) 


210 „ 225 








950 


225 „ 240 








1,080 


240 „ 255 








, 1,250 


255 „ 270 








1,460 


270 „ 285 








1,700 


285 „ 300 








1,1HK) 


300 „ 330 








2,150 


330 „ 3(iO 








2,400 



In the case of a steamship of under 100, or over 3(K) feet, the cubic capacity 
of the lifeboats to be carried shall be prescribed by the Board of Trade. 

Class VI. — Steamships certified to carry passengers on short 
excursions to sea, i.e. beyond partially smooth uxiter limits, between 
\st April and 31st October inclusive, during daylight, and in fine 
weather. 

The registered length of vessel governs tlie number of sets of 



TRADES OF VESSELS AND BOAT ACCOMMODATION 17 

davits to be provided and which are specified in Table V. 
(see below). 

Eachsetof davits must have a lifeboat of Class I. attached to it. 

This class of vessel is also subjected to the provisions of 
General Rule 20 (1) of the Life-saving Appliances Rules, a copy 
of which will be found on p. 6. 

The number of sets of davits need not exceed the number of 
boats required to accommodate the total number of persons 
carried, or which the ship is certified to carry, whichever number 
is the greater. 

The lifeboats must be of reasonable capacity, having regard 
to the size and design of vessel. The boat arrangement must 
receive the approval of the Board of Trade. 

The aggregate capacity of 4he lifeboats need not be greater 
than is required to accommodate the total number of persons 
which the ship is certified to carry. 

If the regulation number of boats is insuflScient to accommo- 
date the total number of persons carried on board, or certified to 
be carried, then additional lifeboats or approved life-rafts, ap- 
proved buoyant deck-seats, or other approved buoyant apparatus 
must be provided, as shall be suflicient, together with the life- 
boats already provided in accordance with Table V., for 70 per 
cent, of the total number of persons for which the ship is certified. 

Class vn. — Steamships certified to carry passengers in partially 
smooth waters. 

The same regulations govern the life-saving equipment of 
vessels of this class as in vessels of Class VI., except that the 
percentage for provision of lifeboats, life-rafts, etc., is 60 instead 
of 70. 

TABLE V. 

Appendix IV. of Jiules for Life-saving Applinncts (1914). 

Minimum Number of Sets of Davits required to be provided in a »Steam- 

SHiP OF Class VI. or Class VII., Home Trade. 

Length of 8teain«Jup iu feet. Mininmm number of HeU of 



Under 200 2 

200 and under 240 .... 3 

240 „ 280 ... . 4 

280 „ 320 ... . 6 



In the case of a steamship of over 320 feet, the number of sets of davits to 
be provided shall be prescribed by the Board of Trade. 

C 



18 SHIPS' BOATS 

Class Vlli. — Steamships certified to carry passengers in smooth 
waters in estuaries and lakes, 

A ship of this class, if not under 70 feet but under 150 feet 
in length, must cany at least one boat ; and if 150 feet or more 
in length, at least two boats. 

The boats must be attached to davits. 

Including the before-mentioned boat or boats the vessel must 
also carry such boats, approved life-rafts, approved buoyant 
deck-seats, or other approved buoyant apparatus, as shall be 
sufficient to accommodate 40 per cent, of the total number of 
persons for which the ship is certified. 

It will be noticed that no particular class of boat is specified, 
and invariably an ordinary boat or boats without buoyancy 
air-cases (Class III.) are suppliedfand fitted under davits. 

There may be particular cases where the arrangements on 
the upper deck are such as to make it impracticable to carry 
out the statutory requirements ; consequently, the Board of 
Trade may, in their discretion, relieve a ship of this class wholly 
or partially from the operation of the rules. 

Class IX. — Steamships certified to carry passengers in smooth 
water on rivers or canals, 

A ship of this class, if not under 70 feet in length, shall carry 
a boat in such a position that it can readily be placed in the 
water. In addition to this boat, the vessel must carry such 
boats, approved Hfe-rafts, approved buoyant deck-seats, or 
other approved buoyant apparatus, as shall be sufficient to 
accommodate 40 per cent, of the total number of persons for 
which the ship is certified. 

A vessel less than 70 feet length must carry boats, approved 
buoyant apparatus, etc., for 40 per cent, of the total number of 
persons certified to be carried ; but here, again, the particulars 
of the vessel's deck arrangements have to be specially considered 
and the matter must be submitted to the Board of Trade, who 
may in their discretion relieve the ship of some of these obligatory 
provisions. 

Class X. — Steam launches and motor boats certified to carry 
passengers for short distances to sea. 

A ship of this class, if over 60 feet in length, must comply with 
the same regulations which govern vessels of similar length in 




I 



Class VIII. of the Home Trade, Vessels of 60 feet in length and 
under are not required to carry boats, but must be provided with 
two lifebuoys, and an approved life-jacket for each person and 
child on board. These provisions are considered sufficient to 
cover all reasonable circumstances. 

Class XL — Sailing boats carrying tnore tlum twelve passengers 
for short distances to sea. 

A ship of this class, if over 60 feet in length, must comply with 
njis regulating the life-saving equipment of vessels iu Class 111, 
of the Home Trade. 

If the vessel is GO feet or under in length, two lifebuoys nmst 
be provided, and an approved life-jacket for each person and 
child carried on board. These provisions are in lieu of a boat. 



Class XU. — Steam fish carriers, tvgs, steam, lighters, dredgers, 
ateam hoppers, hulks, and barges, which proceed to sea. 

A ship of this class shall comply with the rules in Class II. of 
the Home Trade. 

Vessels which are towed from one port to another, say from 
Belfast to Glasgow, for tie purpose of having their machinery 
installe<l, come within the operation of these rules for life-saving 
equipment,- and are considered for the time heini^ as hulks which 
proceed to sen. 

Class XIII. — iSleam fi^sh carriers, lugs, steam lighters, dredgers 
steam hoppers, htdks, and barges, which do not proceed to sea. 

A ship of this class must carry a boat sufficient to accommodate 
all persons on board. 

• General Remarks. — The foregoing quotations are based upon 
the regulations contained in the Rules for Life-saving Appliances 
of 1914, and apply to new vessels, and vessels under construction 
since that date. Various deviations had to be made from these 
rules to suit the retjuiiements of vessels whose keels were laid 
before certain spctritied dates, but reference has not been made 

I in this section to such vessels. 
The writer has endeavoured to use the language of the rules, 
with exphuiatory notes to assist the reader to clearly understand 
the varied — and often confusing — requirements which must be 
carefully considered when preparing the arrangements for 



SmPS' BOATS 

accoiiiniocUtiHg the boats and mstalling the davits. ]t is an 
advantage to the shipbuilder to always submit plans for 
the consideration of the Board of Trade at the earliest possible 
date. 

Each country must draw up its own classification of vessels 
to suit the local conditions, but the principles approved by the 
International Conference on Safety of Life at Sea are now being 
practicallv adhered to by most of the representative nations. 

The regulations issued by the Board of Supervising Inspectora 
of the United States of America, are divided into four parte, viz, 
(1) ocean and coastwise ; (2) great lakes ; (3) lakes other than 
the great lakes, bays, and sounds; and (4) rivers. 

It should be remembered that any boat which forms part of 
the statutory ecjuipmeut of a British vessel, must not be less than 
125 cubic feet in capacity. 

Where it is found impossible in a small vessel to provide 
proper facilities for stowing and handling a boat of this capacity, 
then appUcation must be made to the Board of Trade, who may, 
in their discretion, allow a boat of smaller capacity to be carried 
, on the vessel, provided it is large enough to accommodate all 
persons carried on board. 

This is a question which must be left to the practical experience 
of the surveyor who is dealing with the vosBel. Each individual 
case is dealt with on its merits, for it is obvious in the ease 
of small coasting, sailing, or auxiharj' motor vesseb, that it is very 
difficult to carry out the statutory requirements in their entirety. 

In the United States of America the Uraiting size for ocean and 
coastwise vessels is 180 cub. ft., except in certain classes of 
vesseb under 1000 tons gross, a reduction is made to 125 cub. 
ft., and again where certain steamers of 400 tons gross and under, 
operating within 5 miles of land and there is lack of space to 
properly carry a boat of 125 cub, ft., permission is given for 
a boat of smaller size, but it must be large enough and of suitable 
character to carry every person on board. 



SECTION B.—CLASSU-'l CATION OF BOATS. 

Ships' boats vary m type and design ; but for the purpose of 
appropriating a particular type of boat to suit the requiremeutw 
of each class of vessel; they are divided into two main groups, viz. 
" Opeji " boats and " Pontoon " boats. 

To simplify the administration of the Rules for Life-saving 



CLASSIFICATION OF BOATS 21 

Appliances, the two main groups are split up into three distinct 
classes, viz. — 

Class I. Lifeboats, with rigid sides. 

Class II. Lifeboats, with collapsible bulwarks. 

Class III. Open boats, without buoyancy air-cases. 

To enable boats to be carried on board appropriate to the 
individual design and trade of each vessel, the three principal 
classes are sub-divided as follows : — 

Class Ia. — Open lifeboats with internal buoyancy only. 

This type of boat may be constructed of a single or double 
thickness of wood, or a single thickness of metal. 

The internal buoyancy is provided by watertight air-cases or 
tanks, fitted along the sides or at the ends, but not in the bottom 
of the boat. The ideal position for the buoyancy tanks would 
be to fit them to the height of the gunwale and winged out as 
far from the middle line as the internal arrangements of the boat 
will allow. 

The usual practice is to fit them under the thwarts and side 
seats, the tanks lying close into the form of the bilge ; conse- 
quently, in this position the tanks are not of much material 
advantage towards securing a self-righting boat. The main 
object in fitting the air-tanks is to provide a reserve of buoyancy 
should the boat become flooded. It is a matter of great 
difficulty to right an upturned lifeboat in the water, with the 
buoyancy tanks fitted in the present position, and it is con- 
sidered that the design of the Class Ia lifeboat can be improved 
and made of more practical value, if the tanks are placed as already 
suggested, and good powerful hand pumps fitted at each end of 
the boat. 

A section of the Class I a lifeboat is shown in Fig. 1, and a 
half section or isometric projection is given in Fig. 87, which 
illustrates the general lines pf construction of a wooden boat. 

The material of the internal buoyancy tanks is of copper or 
yellow metal of not less than 18 ozs. to the superficial foot, or of 
other durable material. Galvanised iron or steel has proved 
to be most unmiitable for the purpose. 

In the case of a wooden boat, the internal buoyancy must be 
at least equal to one-tenth of the cubic capacity of the boat. For 
example, if a lifeboat of this class possessed an internal capacity 
of 500 cub. ft., but was only certified for 48 persons, due to 



22 



SfflPS' BOATS 



insufficient seating accommodation, it would still be necessary 
to provide 50 cubic feet of air-cases. 

In the case of a metal boat, an addition is made to the 
cubic capacity of the airtight compartments or cases, so as to 
give it buoyancy equal to that of a wooden boat. Reference 
should be made to Part VI., Section C, for a description of the 
method of obtaining the amoimt of capacity of air-tanks in steel 
boats. 

The number of persons which a lifeboat of this class is con- 
sidered fit to carry, is obtained by dividing the capacity of the 
boat in cubic feet by the standard imit of capacity of 10 cubic 
feet. 

If a lifeboat of Class Ia has a capacity of 500 cub. ft.> 
measured by Stirling's rule, the number of persons assigned 



L.W.L 



1' . 


1 


THWARTS 


' 


r— 1 'l||^ 


1 

AIR 










^'^ 11 


|\ CASES 


y __.. 

% 


LOWER 

• 

■ i 


CROSS SEATS 

1 


1 

J 





Fig. 1. — ^Midship section of Class Ia open lifeboat. 

would be fifty, provided they could be properly seated without 
hindrance to the oarsmen. 

The usual form of an open lifeboat of Class Ia is double bowed, 
but it may have a square stem. The shape of the ends has no 
influence on the class. 

The Class I a lifeboat is considered to be the highest standard 
of efficiency in comparison with other types. 



Class Ib — O'pen lifeboats mth internal and external buoyancy. 

The details of construction and outline of form of this type of 
lifeboat is similar in all respects to that of a lifeboat of Class Ia, 
except that external buoyancy is fitted in addition to internal 
buoyancy. 

The internal buoyancy of wooden boats is made up with 
waterrignt air-cases of copper or yellow metal, the total volume 



CLASSIFICATION OF BOATS 



23 



of which is equal to 7J per cent, of the cubic capacity of the 
boat. 

The material used to form the outside buoyancy is usually 
solid cork, attached to the sides of the boat in the manner de- 
scribed in Section B of Part IV. 

The volume of external buoyancy, if of solid cork, for a wooden 
boat, is not less than thirty-three thousandths of the cubic 
capacity of the boat. 

The divisor or standard imit of capacity used in obtaining the 
number of persons which this class of lifeboat Ls considered fit 
to carry, is nine cubic feet. 

If the internal capacity of a lifeboat is 500 cub. ft., the 

500 
number of persons allotted would be ^— = 55, as compared with 

50 for a Class Ia lifeboat of the same dimensions. 



OUTSIDC 
OOYANCY 




Fio. 2. — Midship section of Class Ib open lifeboat. 

The amount of internal buoyancy would be 7| per cent, of 
500 = 7*5 X 5 = 37*5 cub. ft. of watertight air-cases. 

The amount of external buoyancy, if of solid cork, is therefore 

33 
500 X-^— ^= 16*5 cub. ft., making a total buoyancy of 54 cub. 

ft., being an addition of 4 cub. ft. as compared with that 
required for a Class Ia lifeboat. 

When a lifeboat of this class is constructed of metal, an 
addition is made to the cubic capacity of the airtight com- 
partments so as to make the buoyancy equal to that of a 
wooden boat. 

It has been the writer's experience when allotting the number 
of persons to lifeboats, that in the case of Class Ib boats, the 
seating accommodation is the factor which determines the actual 
number that can be safely placed in a boat, and there is, therefore, 
very little advantage to be gained by fitting the outside buoyancy 



24 



SHIPS' BOATS 



in order to obtain the smaller capacity divisor, viz. 9 as com- 
pared with 10 for the Class Ta lifeboat. 

An outline section of a Class 1b lifeboat is shown in Fig. 2. 

Class Ic. — Pontoon lifeboats having a well deck and fixed 
watertight bulwarks. 

Boats of this type are very rarely constructed for passenger 
steamers ; the Class IIa open lifeboat appears to be the most 
popular, owing to its adaptability for close stowage. 

The characteristic features of this class of boat are that 
the occupants are accommodated above the deck, and it is 
dependent for its reserve buoyancy on the efficiency of 



I 



m 



riXCO THWARTS AND BULWARKS. 




kWC 



Fio. 3. — Midship section of Class lo pontoon lifeboat with well-deck and 

fixed bulwarks. 



the watertight sub-division of the hull, and not upon watertight 
air-cases. 

Non-return valves are fitted in the well for efficiently clearing 
the deck of water. 

When the boat is fully loaded the freeboard must be such 
that provision is made for a reserve buoyancy of not less than 
35 per cent. 

Fixed watertight bulwarks are fitted above the deck, for the 
protection of the passengers, to which are secured the thwarts 
and side seats. 

The design of this class of boat is generally admitted to be a 
good one, having ample stability and giving a fair amount of 
protection to the occupants. The efficiency of the watertight 
compartments depends upon good workmanship, and also the 
careful oversight of the inspector. 



CLASSIFICATION OF BOATS 



25 



The details of construction are dealt with in Section E of 
Part IV., and a midship section is shown in Fig. 3. 



Class IIa. — Open lifeboats having the upper part of the side 
collapsible. 

A boat of this type is constructed of two thicknesses of wood, 
the combination being sometimes larch and yellow pine, but the 
better class and more reliable boats have their hulls made up of 
two thicknesses of mahogany. There is considerable difference 
in design from the pontoon type of lifeboat. 

Reference should be made to Fig. 4 which shows in outline 
the midship section of a Class IIa lifeboat. The reserve 



BULWARK AND THWARTS RAISED 



BULWARK AND THWAfTTS COLLAPSED 




Fio. 4. — ^Midship section of Class IIa open lifeboat with collapsible bulwarks. 

buoyancy is provided by watertight metal air- cases fitted at 
the sides of the boat, and external buoyancy made up of solid 
cork attached in a similar manner as approved for the Class Ib 
lifeboats. 

The wood covering to the buoyancy air tanks forms a partial 
deck to the boat, which provides seating accommodation for the 
occupants. Additional accommodation is given by thwarts and 
side seats which hinge above the deck and become automatically 
secured in position by the bulwarks. 

The bulwarks are made to hinge down on the declc to facilitate 
stowage. 

The internal metal air-cases must have at least 1*5 cubic feet, 
and the external buoyancy of solid cork at least 0*2 cubic feet, 
for each person the boat is able to accommodate. 

There is also what is termed a modified Class IIa Open Life- 
boat. To obviate the necessity of fitting the external buoyancy, an 



26 



SHIPS' BOATS 



addition has been made to the internal metal air cases. Most of 
the Class IIa lifeboats are now constructed on these lines. 

The details of construction and method of obtaining the 
correct number of persons which can be allotted to this class of 
boat, are dealt with in Section D of Part IV. 

Class IIb. — Pontoon lifeboats having a weU-deck and collapsible 
bulwarks. 

The hull of this class of boat is constructed in the same way 
as a Class Ic lifeboat, the only difference being in the type of 
bulwark. To facilitate stowage the bulwarks of the Class IIb 
lifeboat hinge down on the deck. 

BULWARK AND THWARTS RAISED 
STOWING POSITION OF BULWARK ETC 

a. 




U.WU 



Fio. 5. — ^Midship section of Class Ub pontoon lifeboat with well-deck and 

collapsible bulwarks. 

Constructive details are dealt with in Section E of Part IV., 
and a midship section is illustrated in Fig. 5. 



Class lie. — Pontoon lifeboats havitig a flush deck and collapsible 
bulmarks. 

The general arrangement of construction is very similar to a 
Class IIb lifeboat, except that the latter possesses a well in the 
deck and the Class lie has a flush deck. Efficient arrangements 
must be fitted for speedily clearing the deck of water. Two tons 
of water must be cleared from the deck of a boat 28 feet in length 
in 20 seconds, as compared with 60 seconds in a Class Ic or IIb 
lifeboat. Non-return valves or scuttles are fitted in the deck 
and bulwarks, the number of which depends on the experience 
gained from the flooding tests. 



CLASSIFICATION OP BOATS 



27 



Details of construction are referred to in Section E of Part IV. 

Considerable care and oversight need to be exercised on the 
part of ships' officers and inspectors in keeping the pontoon 
lifeboats periodically under a close survey. Usually these boats 
are stowed in tiers, and very rarely come into the operation of 
boat drill. The influence of the weather has a detrimental effect 
on the watertightness of the hull, if the deck is of wood. Boats 
constructed of steel can more easily be divided and each compart- 
ment made independently watertight. Probably the decks of 
such boats are not subjected to the same damaging effect from 
the weather as the wooden boat, but the necessity of periodical 
survey for the prevention of corrosion is just as great in the steel 
boat. 



FLUSH DECK 




7W=* 



ICHT COMP 



I 





^rt|vient 



I t 

I I 



Fio. C. — Midship eection of Class lie pontoon lifeboat with flush deck and 

oollapsible bulwarks 

The American Balsa Company, the successors to the Welin 
Marine Equipment Company, construct a large number of steel 
boats of this class, which are known as the " Lundin " Decked 
Lifeboat ; Messrs. Mechan and Sons of Glasgow have also con- 
structed boats of similar type for the Welin Davit Co. 

Information dealing with freeboard and the method of 
obtaining the correct number of persons that can be assigned to 
a boat, is given in Section E of Part IV. 

A middiip section is shown in Fig. 6. 



Class III, — Open boats which have not the huoyaticy required for 
lifeboats of Class /. 

The construction of this class of boat is identically the same 
as a Class Ia lifeboat, with the one exception that buoyancy 
air-cases are not fitted. If it forms a part of the statutory 



28 



SHIPS' BOATS 



equipment of a vessel, it should be fully equipped in every detail 
as a Class 1a lifeboat. This provision is often lost sight of by 
shipbuilders and boatbuilders. 




Fio. 7. — Midship seotion of Class III. open boat. 

Further reference is made to this type of boat in Section 
C of Part IV. 

A midship section is shown in Fig. 7. 



SECTION C— FORM, STABILITY, STRENGTH, AND 
CAPACITY, OF SHIPS' BOATS. 

FORM. 

It has been the aim of the author throughout the preparation 
of this text-book, to deal essentially with the practical appli- 
cation of the subject, and to avoid all abstruse theoretical 
considerations which would hinder the reader with a Umited 
knowledge of the Science of Naval Architecture, from obtaining 
an intelligent grasp of the main features which have to be ob- 
served in determining a suitable form and general design, before 
commencing construction on a ship's boat which ha§ to form 
part of the statutory equipment of a merchant vessel as a Ufe- 
saving appliance. 

Practice and theory are inseparable, and both must be 
correlatively associated with any attempt to deal in detail with 
the present subject. It would be just as futile and useless to 
commence the building of a house, without previously taking 
the precaution of considering the suitability and strength of the 
foundation, as to discuss the practical details of ship or boat- 



FORM, STABILITY. STRENGTH, AND CAPACITY 29 



l)iiil(lm>; without due reference being given to the main theoietical 
I mvestigationa connected with the deai^n. 

Progreaa in all Engineering Science has been largely due to 
^tlie personal initiative of the "investigator" who has given to 
I the practical man in later years much financial advantage as one 
I of the results of his work and devotion, 

We should, therefore, not think lightly of theory in ite relation 
I to the subject of ships' boata, even if it can only be regarded 
1b6 the "offspring'' of the much larger and more important 
[Science of Naval Architecture. 

As far aa this book is concerned theory has been given it* 
[ correct hcus »tandi in the order of treatment. 

During the past ten years there has l)een ample opportunity 

P provided for students t*) become thoroughly acquainted with all 

^the theoretical considerations associated with shipbuilding, 

I through the medium of many excellent text-books written on the 

isubject. The author has, therefore, kept this section of the 

f treatise within defined limitations, with the exception of that 

portion which deals with initial stability and the influence of 

free water in a boat on its stability, and as tlieuc featuri}s have 

such a regulating influence on Form, the matter has been discussed 

^H at some lei^h. 

^K Form and Stability cannot actually be separated into two 
^^V distinct section.^ lor discussion : one b the outcome of the other. 
^H Before determining the most suitable dimensions for a life- 
boat in order that it may safely carry, ia a seaway, the allotted 
number of persons, it is of importance that we should under- 
fltand some of the salient features which influence the fonu of a 

■ boat. 
There has been too great a tendency in past years for certain 
boatbuilders to fine down the sections of their boats, in order 
to save material, and provide less work in the operation of 
planking. Keen competition in busy shipbuilding centres, 
without the exiatence of a recognised scheme of scantlings or 

I minimum specification, has been responsible for nlany doubtful 
Efeboats being placed on board merchant vessels. 
Very little consideration was given to the undei-watcr form, 
«id the common practice was to build the boat " to the eye " 
without the use of even a midship section mould. A great deal 
depends on the way the garboards or sandstrakes and their 
Adjacent strakes are worked, as to what measure of fullness 
the boat will take. If the rise of floor comes up too quickly 
to suit the breadth, or the bilge planking is worked in surJi 



J 



30 



SHTPS' BOATS 



iiiaiinei- 08 to narrow the Iteaiii of the boat, a too frequent use of 1 
ahores has consequently to be made to preserve the fonn of the 1 
boat, to suit the specified dimensionH. In the effort to save 
matflrial and labour, suitability of form is often sacrificed for 
the convenience of working, and these objectionable practices 
make one often doubt the seaworthy qualities of the boat. 

It is generally accepted among practical men, tliat in order 
to preserve efficient solein^ of the plank !andinj;s, upon wliich 
the watertiji;)itne8a of a boat so much depends, and to maintain 
a parallel breadth for the landings, it is most essential that 
section moulds should be used at amidships and the quarter 
lengths. 

The Life-saving Appliances Rulea of 1913 insisted that in 
open lifeboats of Class I. (they were then known as Section A 
lifeboats) the boat's half-girth amidships, measured outside the 
planking from the centre line of the keel to the top of the gunwale, 
should be at least equal to eighty-eight hundredths of the sum 
of the boat's depth inside and half its maximum breadth amid- 
ships, iM. ^ = 88%, and that the mean of the half-girths 

measured in the same manner, at two points, one quarter of the 
length of the boat from the stem and stempost respectively, 
should be at least equal to eight-tenths of the sum of the 
depth inside and half the maximimi breadth amidships, i.e. 

p*^ !, = «»%■ 

If a lifeboat did not comply with this girth rale, the number 
of persons to be carried was reduced, by dividing the capacity 
of the boat by the larger divisor 12 instead of 10, unless it was 
proved by actual test afloat, with the fuU equipment on board, 
that the boat had sufficient seating accommodation for the full 
number of persons, without interfering with the oarsmen. 

With tlie 1914 issue of the Life-saving Appliances Eides, the 
girth rule was deleted, partly as a result of the recommendations 
of the Departmental Committee on Boats and Davits. 

The girth rule, nevertheless, possessed an advantage wliich 
prevented the builder from fining away the ends of the boat 
after he had secured the correct depth and breadth at the midship 
section. 

For some time there has been a unanimous expression of 
feeling among boatbuilders that there should be some definite 
rule or dimensions given, which would ensiire a minimum fullness 
of form being maintained in open boats of Classes 1. and III. 



I 

I 

I 

1 

I 

1 

1 

1 

I 



FORM, STABiUTV, STKENOTH. AND CAPACITY 31 

While it is considered undesirable tfl place uimetessaiy 
'reetrictionB on design, it is essential that a reasonable amount 
of fullness should be preserved towards the ends of a boat, and that 
a sufficient volume of capacity be provided to adequately support 
the full number of peraons carried. 

Apart from the considerations of stabrlity, it has been found 
necessaiy, with a standard depth for the thwarts to be fitted 
below the gunwale in boats of Classe« I. and III., to preKerve a 
medium rise of floor, alsn that the fulhictss of underwater form 
be carried well forward and aft. in order to " wing out " and 
satisfactorily house the buoyancy air-caaes, without encroaching 
unnecessarily on the space between the tank cleading for the 
reception of the lower aeats. 

Considerable discussion has arisen from time to time as to 
the best form which should be preserved in a boat constructed 
for the purpose of containing a large number of occupants, and 
where arrangemeats are made for the pmpulsion by the aid of 
oars or with the assistance of sails. 

Formation dI Bow.^Atthou^h it is the usual practice to 
avoid the fitting of a bow buoyancy -tank owing to the difficult 
shape for construction, yet it is considered by the writer that two 
long metal air-cases placed in the bow, one on each side of the 
lifting hook, have an important value in providing the boat with 
an easy lift on enterinj; a wave, should a large volume of water 
be taken on board. 

The majority of boate are cunstnicted with their quarter- 
Ivngth sections at the forward and after ends practically alike. 

The bow shoidd be comparatively fine in form to reduce the 
shock of each wave or of a running sea, and the possession of a full 
st«rn steadies the boat and prevents the bow from hammering 
unduly over short waves or rising on end against a high breaker. 

There must be a reasonable amount of surplus buoyancy 
forward, so as to enable the boat to rise to each wave, but not 
enough to lift it high above the wave. In this respect it would 
be an advantage in all open lifeboat^^ of Class I. to have the bow 
tieckeii over for a short distance, as is done in the majority of 
motor lifeboats, which allows the boat to run into a wave and 
rise through it without taking much water on board. 

Formation ot Stern. — The stern should be made with full 
quarters, i.e. continuing the breadth weU aft, with comparatively 
line hnes below the full quartera, so that when the bow is rising 
to a wavC) the broad stem with less surplus buoyancy has a grip 
of the water and helps the boat to maintain headway and stability. 



32 SHIPS" BOATS 

Sheer lias considerable influeace in lielpin^ to preserve 
various qualities referred to. Wliea sailing to w-indward, a good 
broad stem with a moderately line and high bow and a deep 
heav}' keel, provide the boat with many valuable characteristics, 
wliich help to maintain a condition of safety when in a seaway 
with a full load. 

Influence ol Dimensions on Form.^Uitherto, there has becD 
a tendency among the staff of the shipbuilder to use dimensiona 
for ships' boats which are obviously unsuitable to secure the best 
results for stability. A certain number of a crew is carried on a 
cargo vessel, and provision has to be made for supplying boats 
on each side of the vessel, of sufficient capacity' to accommodate 
the total number of persona on board. Dimensions are then 
selected, which, when multiplied together with the coefficient 6, 
give a certain capacity which ia considered sufficient to provide 
the necessary accommodation, and will meet the requirements 
of the Life-saving Appliances Rules. The latitude thus given, 
owing to the absence of any guiding factors, has been responsible, 
in many instances, for dimensions going to the boatbuilder 
whicii the latter knows, frtmi his own practical experience, to be 
moat unsuitable. It very often happens when the effort is made 
to provide accommodation for the whole of the crew in one boat 
on each aide, that the boat ia too large for the crew to con- 
veniently handle. 

In the 1914 issue of the Life-saving Apphancea Rules, it states 
that in working up the capacity of an open lifeboat, the depth 
is always to be limited to 45% of the breadth. This percentage 
has always been a " bone of contention " with boatbuilders and 
shipbuilders ; the former consider, and rightly so, that a depth 
equal to 45% of the breadth does not give such a stable boat as 
one with a depth of iO% or at the most 42% of the breadth. 

The thwarts are fitted at a standard depth below the gun- 
wale, and the weight of persons is kept down in the boat as low 
as will be consistent with the provision of a auflicient freeboard. 

Take a well-known standard size of oj>en lifeboat of Class Ia, 
viz. 24' 0"x 7' O^x 3' 0°. By fitting lower seats, this type of 
boat will accotomodate 32 persons, and no more, without unduly 
interfering with the free use of the oars. This particular depth 
is 40% of the breadth. Suppose the depth is increased to 45% 
of the breadth, it stands to reason that by increasing the depth 
another 4 inches you will not secure another square foot of area 
for the accommodation of an additional person. Although you 
have increased the freeboard 4 inches, the weight or the centre 



I 
I 



I 
I 

I 



FORM. STABILITY, STRENGTH, AND CAPACITY 33 

of gravity of 32 puriKiiiB has beeji raised a siniilar aniimiit, which 
has reduced the metaceutric height. 

As will be seen later on in this section, a certain amount of 
latitude can be j^iven to the underwater form of a bi»at, without 
seriously interfering with its seaworthy i:]uahtics. 

The aim is to find the happy medium between the flat or 
full-formed underwater section aud the section possessing gteat 
rise of floor, which will give a satisfact^try type of boat and suitable 
for the majority of the circumstances in which it may be required 
t" operate. 

CoefBcleat ol Form. — As a result of the accumulation of 
information from various sources, it seems very desirable th(it a 
miuimum coefficient of form should be insisted upon, so that 
some of the difficulties already referred to might be avoided. 
This coefficient is suggested as being not less than Qi. 

The internal capacity of the boat is measured as explained 
on pp. 81-83, and the result divided by L X B X D ; L being 
the lengtii to inside of plauk rabbets measured at the stem and 
atempost, B the greatest breadth at middle of lenjith, measured 
to inside of planking, aud D the depth amidships from to]) of 
gunwale to inside of planking at keel. 

With this limiting coeflicient of form, tlie required amount of 
underwater fullness is assured, but to ask the boatbuilders to 
construct open lifeboats of Class I, and boats of Class III. to this 
required coefficient, without some guiding offsets, would make the 
operation somewhat difficult, unless the dimensions of boats and 
moulds were standardised. 

These oSsets are now in operation, whereby the boatbuilder 
can conveniently and rapidly apply a check to the form of the 
boat aa the planking is in progress. 

Reference is made tn Fig. 18 un page 6,5. 

A water plane level is taken at half the depth amidships, 
and the breadth on this water-line amidships must be '96 of 
the full breadth of the boat, and the breadth measured on the 
same water-line, at the quarter- lengths, must not be leas than 
■77 of the full breadth of the boat. 

Take, for example, a lifeboat of Class Ia with the following 
dimensions : 24'0' X 75' X 30'. 

The breadths measured on a water-line at the half-depth 
amidships would be — - 




Amidships : 7D' X -90 = 72' (7' 2i'). 

At quarter-lengths : 7-5' X ■77 = 5-78' (u' 9)' 



34 SHIPS' BOATS 

Having these pointe fixed in the three sectioDS of the boat, i 
is necessary to consider the most suitable rise of floor, and the 
writer has come to the conclusion after experience with many 
types of boats, that the best underwater form for an open lifeboat 
of Class Ia is obtained by allowing a rise of floor of 5J to 6 in. 
in a half-breadth of 4 ft. 6 in., that is, the beam of the boat 
would be 9 feet. Setting up this rise of floor, as shown in Fig. 18, 
for a 30-tt. lifeboat, the sections for boata of intermediate length . 
between 30 and IC feet, are brought down to this line AB. 

Wallsided topaides are an advantage to the boat in maintaining 
stability, and this is assured by the provision of the '96 offset, at , 
the midship section. 

The Board of Trade recommend in their latest instructions j 
that all open boats of Class I. be constructed with a rise ot £ 
of 6 in. in 4 ft. 

Form of Bilge. ^.Aji easy bilgo is absolutely necessary so as ■ 
to allow for a gradual soleing to be taken off the plank landiQgs. 
A sharp bilge, or one which takes the shape of a ban'el, 
provides a bad form for sailing. 

A sudden breaking off from the wallsided topside to a straight 
rise of floor from the keel, ia detrimental to the sailing qualities 
and stability of a boat, when it is heeled over suddetJy by a gust 
of wind. 

If the midship form gives the appearance ot resembling the 
circumference of a circle, then the boat will be more easily 
inclined when under way with sails set, than if she were designed 
with wall sides down to the half-depth, and po.saeasing an easy 
bilge running into the floor having the amoimt of rise as shown 
in Fig. 18. 

To enable the boatbuilder to readily apply a check on the 
form of his boat as construction proceeds, a table (No, VI.) has 
been drawn up showing the breadths at half the midship-depth 
at the midship section and the quarter-length sections, measured 
to the inside of the planking or the uutaide of the timbers. 
These figures give important spofa in the outline of the sections, 
and with the rise of floor suggested, little difficulty should be 
experienced in making suitable moulds. 

A sudden break from the perpendicular topsides to the floor, 
makes a line of weakness in an open boat in way of the soleing of 
the bilge plank landings, and it therefore becomes necessary to 
increase the thickness of the bilge planking. 

In the case of an open boat of Class I., or, as a matter of fact, 
in any type of boat, one of the weakest spots in the stmcture is 



FORM, STABILITY, STRENGTH, AND CAPACITY 35 

at the bilge, and the strength, to some extent, is made up by the 
fitting of a stringer of the same scantlings as the rising, and 
secured to alternate timbers by through fastenings clenched 
over rooves. 

TABLE VI. 

MiNiHUH Breadths to Inside op Planking at Half MrosHip-DErTH for 

Open Boats of Classes I. and III. 



Dimensions of boat. 


Breadth at midship. ' 


Breadth at quarter- 
0-83' 6' 


length. 


30-0' X 90' X 3-76' 


8r.4' 


8' 6}* 


10" 


29-0' X 8-76' X 3-6' 


8-30' 


8' 3S'' 


6-64' 


0' 


li' 


28-0' X 8-6' X 3-5' 


806' 


8' Of" 1 


6-45' 


6' 


3^ 


27-0' X 8-26' X 3-4' 


7-82' 


r 9r 


6-25' 


6' 


26-0' X 8-0' X 3-25' 


7-68' 


r r 


606' 


6' 


or 


26-0' X 7-76' X 315' 


7-34' 


r 4r 


5-87' 


6' 


lor 


24-0' X 7-6' X 3-0' 


710' 


7' ir 


5-68' . 


5' 


sr 


23-0' X 7-5' X 2-9' 


710' 


r li" 


6-68' 


5' 


sr 


22-0' X 7-25' X 2-75' 


6-86' 


6' lor 


5-48' 


5' 


5r 


21-0'x7'0'x2-7' 


6-62' 


iV ll" ! 


5-29' 


5' 


3r 


200' X 0-75' X2f»' 


(i-38' 


(}' 4r , 


510' 


5' 


ir 


19-0' x6T»'x 2-5' 


614'. 


iv 1 r 


4-9()' 


4' 


lor 


180' X 6-25' X 2-4' 


5-00' 


5' lor 


4-71' 


4' 


8.r 


17-0' X 6-0' X 2-35' 


5-66' 


'y IV , 


4-52' 


4' 


or 


16-0' X 5-75' X 2-3' 


5-42' 


y 5 

1 


4 33' 


V 


r 



Note. — The Board of Trade have adopted the factor -77 for the quarter- 
length breadth as a minimum* owing to the consideration that in very small 
boat8 it is difficult to work the planking to a fuller form. They, however, 
strongly recommend that the breadth of waterplan'3 should be made as great 
as possible consistently with easy w^orking of the planking. 

Owing to the great width in comparison with the depth, 
there is not the amount of latitude in boats of Class Ic, IIa, IIb 
and lie as boats of Classes I a, Ib and 111. for variation of form. 
There does not appear to be much doubt about the dimensions 
of the former as these have been practically standardised as a 
result of repeated stabiUty tests. 

Breadth in relation to Length. — In dealing with the dimensions 
of boats of Classes Ia, Ib, and III. (when the latter form a 
part of the statutory equipment of a vessel), useful formulae can 
now be used which will act as a guide for the boatbuilder and 
the shipbuilder in securing a suitable breadth for a particular 
length of boat. If these are used, it will ensure a breadth 
being worked which, from the results of stability tests, is con- 
sidered to be the minimum for boats of these classes. 



36 SfflPS' BOATS 

The following formulae will serve the purpose of quickly 
obtaining the minimum breadth required, these being in 
accordance with the regulations issued by the Board of 
Trade. 

The breadth of the boat may exceed the breadth obtained 
by these formulae by not more than 3 in., but the depth in 
that case must not exceed that obtained by the recognised 
formula referred to in the next clause. 

For boats 24 ft. in length or over — 

T* 1.1 • r X Length in feet + 6 

Breadth m feet = — ^^ . 

4 

For boats 22 ft. in length or under — 

T» j^i • J ^ Length in feet + 7 

Breadth m feet = r 

4 

For boats between 22 ft. and 24 ft. in length — 

Breadth = 7 ft. 6 in. 

Depth in relation to Breadth. — ^In order to keep the weight 
of the persons as low down in the boat as will be consistent with 
the satisfactory provision made for the use of the oars from the 
thwarts, and at the same time provide a freeboard which will 
ensure a suflScient range of stability, the following formula has 
been adopted by the Board of Trade : — 

T^ .1. • X X '42 (length in feet + 6) 
Depth m feet = ^ — ^ — j — ^ 

Before leaving the subject of Form, reference is made here 
to the Welin Patent Overframe Type of davit, which allows the 
boat to stow in the inboard position, on chocks secured to the 
davit. It is essential, when lifeboats are to be stowed in these 
davits, that dimensions should be taken from the drawings 
supplied by the firm, giving the correct curvature of the arms, 
to enable the boats to lie " neat and snug " to the shape of the 
davit arm. 

Advantages of Standardisation. — The writer shares the opinion 
of many shipbuilders and boatbuilders, that a great improvement 
would be effected if boats of standard dimensions were 
recognised and worked to, provided certain salient features asso- 
ciated with a suitable form were duly observed. 

Such a scheme would considerably increase the output, and the 
boatbuilders would be limited to a smaller number of midship 
and quarter-length moulds. The firms would then be able to 



^^ FORM. STABILITY, .STRENGTH. .VND CAPACITY 37 

standardise all tLfl moulds for cnmhinatioiis, such as deadwooda, 

Iapruns. etc. Material could be ordered iu aaticipatiou of re- 
quirements and with less risk of mistakes. 8t4^ck boats would 
Ibe laid down in jrreater numbers and be ready for emergencies. 
Uakers of patent davits could standardise their fittings with 
ipeater certainty of being able to provide for the full load, and 
the work of the shipbuilder would be lessened through having 
detinite data on which to base the calculations for the size of 
davits. 
The Admiralty have, for many years, worked to a fixed 
Btandanl for dimensions, to suit each particular type of boat, 
A complete set of lines is given to the boatbuilder, which makes 
it necessary for him to lay off the offscta on a scrieve board, in 
preparation for the moulds. The specification is complete in 

» every detail and calls for the highest class of workmanship. A 
comparison between Admiralty and Mercantile boats will 
serve no useful purpose : the former are designed to give easy 
lines for rowing and sailing, they are not fitted with buoyancy 
tanks, and the crews are skilled in all the details associated with 
the handling of a. boat, 

Merchant ships' boata are heavy in scantling, full in form, 
|,.ftnd are designed to meet the heavy stresses imposed when 
bwered from the davits with the full load, and also in the case 
f,ti a Ufeboat lowered in an emergency from a passenger vessel, 
where the majority of the occupants would be undisciphned, 
■ probably in a condition of panic, and ignorant of the manage- 
ment of a boat in a seaway. 

Snitable Dimensiom. — A list of suitable sizes for open boats 

[ Claeaee Ia. Ib, and 111., has been drawn up and shown iu 

Table VH. These size^ will cover all the requirements of the 

iupbuilder between boat« of 16 and 30 feet in length. They have 

sen framed with the purpose of allowing tlie boatbuilder to 

e the smallest number of section mouhls. 

Ill column 1 the dimensions are shown in feet (decimals), 

1 boatbuildcrs are recommended to accuat4)tu themselves to 

e of these figures, as they simplify calcidations. 
In column 2 the same dimensions are shown in feet and inches. 
(\)hitmi 3 gives the capa<?ity of each boat, based on the 
L X B X I) X 0*0 formula. If meaaiu-ed by the cuirect method of 
Stirling's Rule, the capacity should be greater, but iu the 

I majority of caseu the boats will not take more pers<]D3 than that 
given by the use of the first-named rule and the correct unity 
pf capacity. 



38 SHIPS' BOATS 

The numbers ffiven in columnB 4 and 5 are entirely dependent 
on the provision of proper seating accommodation, without unduly 
interfering with the free use of the oars. 



. . C»p«cltTln 1*0. of m 

stun.) cnWctMt. — - - - 



(I) 



3-75' 



•2«-U'x8-75'x3-<l' 

3»0'X»75'x3n' 
•2H-0'x80'x3-5' 

37-«'x8-5'>:3-4' 
•27i''x8-25'x3-4' 

2llO'xH'2r>'x3-25' 
•2iCO'xB0'x3-25' 

2r.0'xH-0'x315' 
•2511' X 775' X 315' 

21-0'x7-7ft'x3-O' 
•21tl'x7-6'x3-0' 
•2:h)'x7-5'x2'«' 

22-0' X 7-5' X 2-75' 
•230'x7'25'x2-7C' 

210'x7-20'x2-7' 
•2rO'x7-0'x2-7' 



X3'4J' 



(2) 
3f>' V X9' if X3' Vf 

au'Cxro-xS'?!' 
ao'o*x8'i»'x3'7r 

2B'0'x'''n'^'''" 

?8'0-x 

ZTtTx 

27' 0* X 8' 3' > 

2«'0'x8'3*x3'3' 

aircxB'irxs'S' 

25'0'x8'0-x3'lS' 
31.'0*x7'll*x3'13* 
24'0*x7'0'x3'(r 
24'0'xTfi'x3'0' 

23'0'xTli*x2'10i' 

22'0-x7'0'x2'B' 

22'U'x7'3'x2'ir 

2rO'x7'3'x2'83' 

2l'0-xT0'x2'8r 

20'0'xT0'x2'7r 

20'0*x6'l)'x2'7i' 

Ht'0*xtr(!-x2'(i' 

IH'O-x0'»'x2'4J'' 

17'0'xfi'0'x2'4i'' 

lll'U*xo'ir'x2'3ii* 



127 



12 



SugiffBtcd iitandtrd Sitcs. 

boaU of Clfua III. ^ 10. 

IS Ib ia Column 6 dfiMmda ui 



Unit of capacity for liffboatn of Clans 1a and 

Unit of oapMily tor lifuboaUt ot i'U^n u li. 

Number ol iM-raons given for lifcbiisls of Ola 

the provision of proper seating iiocontmDdation. 

There is, however, uo reason why this list could not be limited 
to the 8uggest<Hl standard sizes. It ia a short-sighted policy to 
cut down the accoiuiiioilation in the boats to the barest limits. 
The writ«r Is hilly aware of the difficulti.-s to timl Milhrli'iit deck 
space for the boats, particularly those which must be placed 
under davits in a large passenger liner ami the previous remarks 
apply more directly to the ordinary cargo vessel. 



FORM, STABILITY, STRENGTH, AND CAPACITY 39 

A limiting capacity of 125 cub. ft. is placed on a boat which 
is carried on a vessel and has to comply with the requirements 
of the Life-saving Appliances Rules. 

If it is not practicable or reasonable in any case for a ship to 
carry a boat of the minimum capacity prescribed by this rule; 
the Board of Trade may, in their discretion, allow a boat of 
smaller capacity to be carried by that ship. 

In small " puffers " and coasting boats running a short 
distance beyond the smooth water Umits, it is often found 
impracticable to carry a boat of the following dimensions, viz. : — 
16' 0" X 5*75' X 23', which gives the limiting capacity of 125 
cub. ft. 

In Table VIII. is shown one or two suggested sizes for small 
lifeboats of Class Ia and boats of Class III., but it must be clearly 
understood that the number of persons which may be safely 
allotted to these boats can only be ascertained after actual 
trial, for it is the writer's experience that, with the amount of 
equipment which is required to be placed on board, serious 
interference is made with the seating accommodation. 

TABLE VIII. 

PABTICITLABS OF OPKN LiFEBOATS (ClASS 1a) AND BoATS OF ClASS III., 
BELOW THE LlMITINQ CAPACITY OF 125 CUBIC FkBT. 



Dimensions in feet 
(decimals). 



(1) 
15-0' X 5-5' X 2-3' 
140' X 5-35' X 2-25' 
130' X 5-25' X 2-25' 

12-0' X5CX 2-2' 



Dimensions in feet and 
inches. 



(2) 
li>' 0^X5' 0^ x2' 3r 
14' O^'xS' 4rx2' 3"" 

13' o^'xo' r x2' r 

0" x2' 2}" 



12' O^'xS' 



Cai)aclly in 
cubic feet. 

LxBxDxOC 



(3) 

113 

101 

92 

79 



Appro3cimate 
No. of persons. 



(4) 
9 
8 
7 
5 



Note. — Application must be made to the Board of Trade before construction 
is commenoed on any boat below tho capacity of 125 cubic feet, for permission 
to use the proposed dimensions. This action is taken only in the case of 
a boat forming a part of the statutory equipment of the vessel. 



Table IX. indicates dimensions of Pontoon lifeboats of 
Classes IIb and lie and open boats of Class IIa, which have 
been supplied to passenger vessels. 

Table X. gives a comparison between inches and decimals of 
feet, which may prove useful in transposing from one to the 
other, when dealing with dimensions, etc. 



40 



SfflPS' BOATS 



TABLE IX. 
Dimensions of Class IIa Open Lifeboats. 



24' 
26' 
28' 
28' 
28' 
28' 
30' 



xT if xr or : 

x8' or xv iir 

X 7' e* X 2' 2i^ 

X 8' 0* X 2' 2r 

(T X 8' 5^ X 2' 2|' 

0* X 9' 0* X 2' ^' 

(T X ft' 0* X 2' 2r 



0" 

or 
or 



43 persons. 

48 

60 

64 

67 

60 

(54 



Dimensions of Class II b Pontoon Lifeboats. 

2f)'0' X 8-0' X 2' 0' = 66 perepns. 
280' X 8-6'' X 2' r = 63 
30-0' X 9-0* X 2' 2" = 70 



»» 



»» 



Dimensions of (?lass lie Pontoon Lifeboats. 

260' X 8-0' X r 8r = 52 persons. 
28-0' X 90' X r 9* =63 
300' X 9-0' X r lO' =67 



♦t 





TABLE 


X. 






Inches. 


Feet (decimals). 


Foet (decimals). 


Inches. 


1 


•02 




•06 


i 


i 


•04 




•10 


lA 


i 


•06 




•16 


n 


1 


•08 




•20 


2| 


2 


•17 




•26 


3 


3 


•25 




•30 


34 


4 


•33 




•36 


*i\ 


6 


•42 




•40 


4} 


6 


•50 




•46 


5i 


7 


•68 




•50 


«i 


8 


•67 




•56 


Of 


9 


•75 




•60 


7A 


10 


•83 




•65 


n 


11 


•92 




•70 


8J 


12 


100 




•75 

•80 
•85 
•90 
•95 

1 -fUl 


1) 

»s 

103 

11? 

10 



STABILITY. 

In the proper order of things, stability should have been 
dealt with before the subject of form, because it is due to in- 
formation obtained as the result of stability tests that we are in 




FOKM. STABILITY. STRENGTH. AND CAPACITY U 



a position to disciiBB certain salient features whicli aSect the 
' shape and dimensions of ships' boats. It suits the purpose of 
b this text-book, however, to proceed on the present lines. 

It is essential to refer to some of the rudimentary principles 
I which govern the general question of stability. 

When a boat is inclined from her position of reet by some 
t external force, such as the effect of wave motion or wind pressure 
Con the sail area, there is an inherent quality possessed by the 
I "boat, which at once comes into operation in opposition to this 
I>«xtema1 force, tendir^ to move her back to the original upright 
■ position. 

The power which tends to upset the boat is the dynamic 
f force, and the opposing quality to inclination possessed by the 
I boat is a static force. These two forces are always in operation 
i during the period a boat b in a seaway, and when the dynamical 
B forces are in excess of the statical forces, then the boat capsizes. 
The volume or amount of this statical fjuality, or as expressed 
I. in technical phraseology, the moment of the force which is being 
[ exerted to bring the boat back to her position of rest, is the 
I measure of her .stability. 

In order to obtain the most suitable form for a boat to ensure 
that she will possess sufficient stability to enable her to stand 
up against the effect of heavy seas and sudden squalls of wind 
when carrying her full complement of persona, it is necessary 
that we take into consideration the various factors which have 
i a direct bearing upon this measure of stability. 

In other words, we have to find out " what to put into the 
Kboat" as affecting dimensions, weights, and form, which will 
■give the greatest measure of statical stability to enable her to 
rcont«nd against, and overcome ail reasonable dynamical forces, 
' she will meet with, when afloat. 

Displacement. — When a boat is floating freely and at rest 
in still wat€r, she displaces a certain amount of fluid, which, if 
weighed, must equal the weight of the boat, equipment, and the 
lumber of persons on board. 

The amount of the displaced water is termed the boat's 
* Duplacement." and ia expressed as a volume in cubic feet, or 
BB a weight in tons. 

Thirty-five cubic feet of displaced fluid, if salt water, equals 

CHo that if a boat weighed 5 tons, including the full 
it and number of persons, the vrilurae of di»place<l salt 
ist be 175 cub. ft. 
''olume, or internal capacity of an open boat, referred to 



I" 
si 

in 8 
^Hnuffl 

llf as a 



42 SHIPS' BOATS 

in the Rules for Life-saving Appliances, when used for obtaining 
the number of persons a boat can accommodate, must not be 
confused with the volume of displacement. 

Buoyancy. — The support which the boat secures from the 
fluid in which she is immersed comes from the effect of pressures 
which are being exerted at right angles to the surface of the 
planking, and is termed buoyancy, or in other words, a boat's 
buoyancy is her " power to float." 

The point in which all these fluid pressures are concentrated, 
or the resultant of all the fluid pressures bearing on the ship, acts 
through a point, and in a direction vertically upwards. This point 
is termed the '* Centre of Buoyancy'' or expressed in simpler form, 
it is the centre of gravity of the displaced fluid. 

The centre of buoyancy, therefore, depends upon the form 
of the underwater portion of the boat. 

If a boat is loaded with additional weight, the volume of 
displacement is increased, and the distance of the centre of 
buoyancy from L.W.L. is consequently increased. 

In a boat with a sharp rise of floor, the centre of buoyancy 
is relatively higher from the keel than in a boat with a fuller 
underwater section. The finer form makes it necessary for the 
boat to float at a deeper draught, in order to obtain sufficient 
displacement equal to its weight. 

Reference will be made later to this condition, as it has an 
important bearing on the subject. 

If the boat is inclined transversely, the centre of buoyancy 
moves out in the same direction in which the boat ls inclined. 

One of the first conditions which must be fulfilled for a boat, 
when floatuig freely and at rest in still water, to remain in stable 
equiUbrium is, that the weight of the water displaced must 
equal the weight of the boat. The following or second condition 
is, that the centre of buoyancy must be in the same vertical 
line as the centre of gravity. 

Fig. 8 shows the relative positions of the centre of gravity 
** 6 " and the centre of buoyancy " B ," generally found in a 
loaded open boat of Class Ia. The boat is floating in stable 
equiUbrium, with the buoyancy and weight acting in the same 
vertical line. 

It has already been stated that the weight of the di8placed 
fluid in which the boat is immersed, must equal the weiglit of 
the boat, ix. there must be sufficient buoyancy to support the 
weight of the boat. If the boat is damaged below the load 
water-line, and water is taken on board, then she has to draw 



FORM, STABILITY, STRENGTH, AND CAPACITY 43 

upon the remaining intact space above the water-line, to keep her 
afloat. 

This intact volume is termed " Reserve Buoyancy,'' and the 
amount of this volume has a very direct bearing on influencing 
the design of lifeboats. 

Centre of Gravity. — The position of the centre of gravity is 
entirely controlled by the distribution of material or weights, 
and may be described as the point through which the weight of 
the boat, when at rest, may be supposed to act in a direction 
vertically downwards. 

In Fig. 8 we see that the upward supporting forces are acting 
through the centre of buoyancy, and the downward force of weight 



w 



3 


' 


^ 


c 












■< 


^G 




1. 


A 






i 


rj'-' 




-< 


^B 


_y 




\ 


^ 







w 

Fig. 8. 



is acting through the centre of gravity, and both are in the same 
vertical line. 

It is important to remember that when inclining a boat from 
her upright position, and pro\4ded no weights have shifted or 
persons moved, the centre of gravity remains stationary at its 
original position, but the centre of buoyancy moves out in the 
same direction in which the boat is inclined, due to the modified 
form of the underwater portion of the boat as a result of 
the inclination. 

If weights or persons on board are moved in a longitudinal, 
transverse, or vertical direction, the centre of gravity will 
evidently move in the same direction as the weights or persons 
are moved. 

Fig. 9 represents the result of moving several persons from 
one side of the boat to the other, in a transverse direction. 
Assuming the weight of the persons moved as 6 cwts. (w), the 



44 



SfflPS' BOATS 



distance moved through, 7 ft. (d), and the displacement or 
weight of boat 140 cwts. (W), the centre of gravity of the boat 
will move in the same direction and in a line parallel to the 
shifted weight, by the following amount : — 



wxd 



= GG' 



6x7 
140" 



42 
140 



•3 ft. 



The centre of gravity of a person in a sitting position is taken 
as 12 in. above the thwart or side bench. 

In Fig. 9 it will be seen that when the centre of gravity 
moved to its new position due to the shift of weights already 
on board, the centre of buoyancy also moves to a new position, 




B', due to the alteration of underwater form, and the boat is 
brought to rest at a certain incUnation when the buoyancy and 
weight are acting in the same vertical line through B' and G' 
respectively. 

Referring to Fig. 10, a weight already on board is moved 
from the thwarts to the lower cross seats. In this case the 
centre of gravity of the boat is lowered in a vertical direction, but 
the centre of buoyancy retains its original position, owing to no 
alteration taking place in the draft or underwater form of boat. 

Assuming the weight moved being 6 cwts. (w) and the distance 
moved through, 1*5 ft. (rf), then the centre of gravity will be 
lowered in a vertical direction by the following amount : — 



wxd 
W 



-GG' 



6 X 1-5 
140 



9 
140 



•0G4 ft. 



FORM. STABILITY. STRENOTH. AND CAPACITY 45 

1( a weight iii added to tlie boat, its poaitiuii is noted in relatiou 

to the orif^nal centre of gravity of boat. Then, the added 

weight miittipiied by it« dbtance from the centre of gravity and 

divided by the displacement phis the added weight, will give the 

I distance G' the new centre of gravity has moved, i.e. — 

W + w 
Sitppotting an additional weight o( G cwte. is placed on the 





1 


w 




C 






-r-^- -^ 


--4- 












»t 




i 


i- 






..... 


^-M 


W 


r 










^ 




9 


Vy 



Smrts 1'5 ft. above the centre of gravity G, then tlie new 
centre of gravity G' will be raised 062 ft. 

"'X'^,=l=i_l:-'= 1^-062 ft. 

W4-H' 140 + 6 H6 

If the weight is placed on the lower seats r5 ft. below the 
centre of gravitv G, then the new position of the centre of gravity 
G' will be 062 ft. lower than the origmal G. 

In the same way we can ascertain what will be the effect on 
the centre of gravity if weights are taken out of the boat, by 
using the same formula, except that the weight taken out (wi) is 
subtracted fi'oin the original displacement, thus— 



From the foregomg it will be seen that the centre of gravity 
of a boat does not move from its original position unless some 
portion of the weight ahready on board is shifted, such as tJie 



46 SfflPS' BOATS 

transference of persons from one side seat to the other, or 
weights are added or taken out of the boat. 

The position of the centre of gravity is entirely dependent on 
the distribution of weight. 

The position of the centre of buoyancy is altered whenever a 
change of draught takes place or the underwater form of the boat 
changes as the. result of the boat being inclined. 

The relative positions of the centre of gravity and the centre 
of buoyancy have a very direct and important bearing on a 
boat's stability. 

To increase the initial stability the weight added to a boat 
should be placed well below the centre of gravity, or weights 
already situated above the centre of gravity must be removed 
to a position below. (See also " Effect of internal water with a 
free surface," p. 51.) 

In this connection it is very desirable to provide as many 
lower seats as the internal arrangements of the boat will 
allow. 

The thwarts and side benches are kept low enough to be 
consistent with the necessity to make the oarsmen feel comfortable 
and allow them to pull with ease. 

Further detailed reference is made to the question of the 
position of the thwarts and their relation to the stowage of the 
watertight air-cases, in Part IV., Section A. 

Metaeentric Height. — Reference now is made to Fig. 11. 
The figure represents the midship section of an open boat, 
slightly inclined from the upright position. 

The weight of the boat acts in a vertical downward direction 
through the centre of gravity, and the latter does not move 
from its original position when the boat is upright. The 
portion between WL and WL', viz. WSW, which originally 
was immersed, has now emerged from the water, and the opposite 
action takes place with the wedge portion LSL'. The^e wedge- 
shaped portions are equal, because the volume of displacement 
remains the same after inclination, as before. The centre of 
buoyancy, however, has moved out in the same direction as the 
boat is inclined, and takes up a new position B'. The forces of 
buoyancy are now exerted in a vertical direction upwards, through 
B'. As the weight of the vessel is still acting through the centre 
of gravity, and the centre of gravity and the centre of buoyancy 
are not in the same vertical line, one of the conditions for a boat 
to float freely and at rest in stable equilibrium is not being 
fulfilled, and it therefore shows that there are two conflicting 



FORM, STABILITY, STRENGTH, AND CAPACITY 47 

and opposite forces in operation, i.e. buoyancy in one direction 
and weight in another, thus producing what is termed a " couple." 

Where the vertical line passing through the centre of buoyancy 
B', in the inclined position, intersects the original vertical line 
passing through B in the upright position, at a point M, this 
point is termed the Metacentre. 

The distance between G and M (for small angles of inclination) 
is the Metacentric Height or G.M. 

When the boat is inclined longitudinally, the same factors 
come into operation as explained for a boat inclined transversely. 
In the case of a ship's boat, transverse inclinations are more 
easily produced and become of more importance than fore-and- 




aft inclination, and attention will, therefore, be centred on this 
condition throughout this section of the treatise. 

When deahng with small angles of inclination up to about 
12° or 15^, the forces of buoyancy acting along the vertical line 
through the centre of buoyancy are assumed to pass through the 
metacentre M, a fixed point; but at larger angles of heel the 
metacentre and the forces of buoyancy are not in the same 
vertical Une. 

Stability Levers. — If we draw a line through G at right 
angles to the vertical line passing through B', cutting it at Z, we 
obtain the length of the stability lever GZ, or arm of the couple, 
which, when multiplied by W, the displacement, or the weight of 



48 SHIPS' BOATS 

tlio boat with load, will give iis the ''Moment of statical 
HtHhilltjiy^ a force which is in operation to move the boat back 
to it,s original vertical position of rest. 

This property or moment depends on the design and form 
of the boat, and must be equal, at all times, to any external or 
dynamical force tending to upset the boat. 

If the upsetting force becomes greater than the range of 
statical stability the boat will founder. 

The relative position of G to M has a very important bearinir 
on the length of the stability lever. 

The nearer the centre of gravity is brought to the metacentre 
it follows that the initial stability becomes increasingly less 
and when M falls below G the boat is unstable, unless when 
heeh'ng over she draws upon some reserve buoyancy and remains 
sUible in this inclined position, and on being further inclined she 
picks up a sl^ibilitv lever which allows her to heel over to a greater 
angle in safety. 

Su(^h a ciiso is given in Fig. 20, where the stability curve " V " 
is plotlcHi out for a pontoon lifeboat of Class IIb, which 
f^uiiporarily took on board a quantity of water, and in the initial 
inclin«Ml position the metacentre was brought down below G 
whi<'h condition was rovei-seil on further inclinations, imtil her 
maximum stability was reached at about 23"^ of heel. 

Conditions of Equilibrium. — It will not be out of place at 
lliiH point in the treatment of the subject to make a statement 
of the three cimditions which must be fuliilled for a boat to float 
freely and at rest, in a conditiim of stable equihbrium, viz. : — 

(I) The weight of the water displaced must equal the total 
wj'i^'ht tif the h<int, including e«|uipment and the number of 
penums on board. 

('J) The nMitre of gravity of the boat must be in the same 
vrrlinil hm* as the centn* oi bmnancv. 

(W) The rentn* c»f gravity must be beK»w the metacentre. 

Thr iiiel jireni ric met hoil of tindinu the value of a boat's stability 
iM only iipphtjibh* up to angh»s of inclination of about 12° to 15°, 
iiimI Im'noiuI Ihesr angles other methods have to be adopted to 
rnnhjn Mm' leui'lh of stabilitv levers to be accurately calculated. 

Monirnl of Inortla. The ili>tance between the centre of 
iMiMviimv iind the fiMusverse niotacentie is obtained by dividing 
Ihr niMinnit t»l nieiliji o\ the watoi-plane ^I), at which the boat 
iM liniiiiiiM, liv (he Nohmie of ilispl uement (\ ). i.e — 



I 



I 



FORM, STABILITY. STRENGTH, AND CAPACITY 49 

111 moviiiji B weight iiiim one aide of tlie boat to the other. 
or from the thwarts to the lower seats, a moment waa brought 
into operation which afiec'ted the position of the centre of gravity 
of the boat, and this weight, multiplied by the distance moved, 
was the majfnitude of the moment. 

If we divide the watei-plane area into a number of in- 
finiteeioially small parta and multiply each by the square of 
its distance from a given axis, the sum of all these products yive 
what is termed the "Moment of hierlia" of the water-plane 
about that given axis. 

Just as the disposition of weights affects the position of the 
centre of gi'avity, ao the moment of inertia has a direct bearing 
on tlie position of the metacentre. 

If we increase the area of the water-plane the moment of 
inertia becomes larger. 

If we increase the volume of displacement the centre of 
buoyancy ia raised from the keel. 

Therefore, in a wall-sided type of boat, when floating at. 
a deeper draught through the addition of a number of persons 
placed on board, the area of the water-plane and the moment 
of inertia practically remain constant, while the centre of 
buoyancy rises nearer the metacentre. There are also other 
conditions which come into operation and mfluence the centre 
of gravity and, therefore, also the metacentric height, a phase of 
the subject to which further reference will be made later on in 
this section. 

Within the limits of inclination refeired to, the length of the 
stability lever, GZ, can be calculated for each consecutive angle 
ol heel by multiplying the metacentric height, GM, by the sine 
of the angle, i.e. — 

GZ = GM.8infl (See Fig. 11.) 

The length of these level's are set up t^ a convenient scale 
on & base line representing the various degrees of inclination, 
and a curve passing through these spots will give us a " curve 
of statical stability" or what is generally referred to as the 
" glabiliiy curve." The true measure of a boat's stability ia the 
magnitude of the stability m<iment, so that the levers have to be 
multiplied by the weight of displacement W. 

When dealing with boats in varying conditions of " swamping," 
I.e. having on board changing volumes of internal water with a 
free surface, a true comparison can only be made by plotting 
of stability moments. 



50 SHIPS' BOATS 

One or two specinieji staLility curves are sliown in ¥ig. 20, 
The one marked R repreeents the njeasure of stability of an open 
boat of Class Ia. At 0", in the upright condition " A," the boat 
ie assumed to be floating in stable equilibrium, i.e. with the centre 
of buoyancy and the centre of gravity in the same vertical line. 
Immediately the boat is inclined the centre of buoyancy moves 
out to another position, while the centre of gravity remains at 
its original position, when the stability lever GZ comes into 
operation. At the position " B " we see that the gunwale is 
brought to the water-level and any further inclination would 
allow the water to enter and capsize the boat. The angle of 
maximum stability is reached at 28^. If we were able t^ ht a 
watertight deck at the gunwales and retain the original dimen- 
sions, we should probably find that the maximum stability lever 
was not increased by further inclinations, but the watertight deck 
would have considerable effect on lengthening out the range of 
stabihty. 

The vanishing angle of stabihty is reached when the centre 
of buoyancy and the centre of gravity are again in the same 
vertical line as indicated at " C." Any further inclination from 
this position would produce a statical moment operating in the 
same direction as the dynamic or upsetting force, t.e. the position 
of Z would be to the left of G, and the lengths of GZ would then 
have to be plotted below the base line. 

Initial stabili'g is the stability of a boat in its upright condition. 

Increasing the beam of a boat considerably iufluencea the 
initial stability and produces a greater metacentric height, 
because the position of M largely depends on the moment of 
inertia of the water-plane. 

It will be noticed that pontoon boata of Classes IIb and lie 
and open boats of Class IIa have a large metacentric height, 
owing to special features of their design. 

Freeboard has no influence on the initial stability unless 
there is tumble-home or flare-out to the sides, which will have 
an effect on the moment of inertia of the water-plane. It lias a 
direct bearing on the range of stability. The question of free- 
board has to be considered in relation to the centre of gravity 
of the load, and whether the boat is of the ojien or the pontoon 
type, the latter possessing a watertight deck ; open boats of Class 
I [a and pontoon boats of Class IIo are governed by a minimum 
freeboard. Pontoon boats of Classes Ic and IIb must have a 
minimum freeboard which will give them a reserve buoyancy of 
at least 35 per cent. 



I 



I 



FORM, STAB11,ITY, STRENGTH, AND CAPACITY 51 

Open boats of Classes Ia and Ib must have Butfieient free- 
board as will allow them to bo inclmed, under sail, with their 
full comploDient of persona on board, to a reasonable and safe 
angle of heel. Freeboard must be considered in relation to the 
centre of gravity of the persons sitting or standing. Persons 
sitting oil the thwarts of an open boat of Olasa Ia make very 
little diilerence to the centre of gravity of the fully-loaded boat 
when they stand on the bottom boards, but in boats of Classes 
Ic, IIa, IIb and IIo it is imperative, ia their own intereata, for 
persons to retain their seats in oider to maintain the maximum 
stability qualities of the boat. 

As previously explained when dealing with the question of 
form, it is essential inopen boats of Classes I A, Ib, and III. to work 
to a suitable breadth, with a reasonable freeboard, and keep the 
weight down in the boat as low as possible. The inclination oi 
the stability curve to the base line gives us a vei^' good idea 
of the initial stability of a boat, the more obtuse this angle 
becomes the greater ia tiie initial stability ; so that we notice 
with the pontoon lileboats and open boat.8 with collapsible 
bulwarks, that their stability curves rise, from 0", above the 
curves of an open boat of (.'lass Ia, owing to their greater meta- 
centric height. 

The condition " C " in Fig. 20 was only inserted for the 
purpose of illustration, but it is reasonable to imagine that such u 
boat will bo of great value as a life-saving apphance. The depth, 
of course, woidd have to be increased for the satisfactory accom- 
modation of the persons to be carried. Boats that incline to large 
angles would have the effect of pitching the occupants off the seats 
and thus bring mU> operation a moment tending to capsize. 

However, such a boat has been recommended by the Boat* 
Bud Davits Committee, and with these features in view the 
Welin Davit and Engineering Co,, Ltd., have designed special 
boats, illustrations of which are shown in Figs, 130-132. 

EReet of Internal Water with a Free Surlace. — The efiect of 
free water in a boat on the stabiUty is of very great importance, 
particndarly in the Open Classes. With the pontoon lifeboats 
provision is made for quickly clearing water taken over the 
gunwale on to the deck, by fitting special drain valves. 

Very instructive papers were road before the Institution of 
Maval Architects in 1912 and the Institution of Engineers and Ship- 
builders in Scotland in 1913 by the late Mr. A. Cannon, R.C.N.C., 
H.I.N,A., giving the results of his investigations regarding the 
effect of an internal free fluid upon the initial stabiUty and 



1 



52 SHIPS' BOATS I 

stability at large angles, in ahijra of various forms. Mr. Cannon I 
was good enough to allow the writer full opportunity to use I 
these papers for publication in the present treatise, as the subject I 
is 80 closely associated with, and has a direct hearing on, the I 
design and construction of ships' boats. I 

Watertight air-cases are fitted in a boat to increase the I 
maximum righting moment, by I'edueing the moment of inertJa I 
of the free surface of water, and also to provide a reserve of I 
buoyancy should the boat become flooded. I 

When water is first taken over the gunwale into an open I 
boat the added weight is below the centre of gravity, and for I 
tjie purpose of a basis for argument, we will suppose this added I 
weight of water to be fixed, tie effect of which will be to increase 1 
the initial stabihty by lowering the centre of gravity of the J 
boat. J 

Considering the water as free, the metacentre is immediately J 

influenced by the value „, i.e. the moment of inertia of the free ] 

surface of water, divided by the volume of displacement of the I 
boat. As the amount of water increases in the boat, the moment of ] 
inertia (i) practically remains constant, being limited between j 
the vertical sides of the buoyancy air-casea. The weight added j 
below the C.G. increaaea and tends to lower the latter. 

In the first place, there is a reduction in the metacentric 
height, but eventually, with a certain incre-ased quantity of 
internal water, which has the e£Eect of lowering the centre of 
gravity, the original metacentric height is recovered and as 
further quantities of water are added it increases until it reaches 1 
a maximum height, when the water-level inside the boat is the ] 
same as. the water-level outside. 

It does not always follow that because a weight is placed 
below the centre of gravity the metacentric height is necessarily 
increased, because an account must be taken of the metacentre, 
which has changed its position with the increase of draught. 

As the eSect of internal water with free surface increases the I 
initial st^ability uf a boat between certain points, its eSect on the I 
curve of stability and the range apparently grows less, so that J 
in the condition already referred to, when the height of the watoi J 
inside is the same as that outside the boat, giving maximum I 
initial stability, the statical stabihty at finite angles is at i 
minimum. 

Initial Stability. — The following deductions are taken from-V 
Mr. Cannon's investigations on the effect uf an internal freofl 



FORM, STABILITY, STRENGTH, AND CAPACITY 53 

fluid on the initial stability of a vessel, and made applicable to 
the conditions of a ship's boat : — 

(a) Consider the vxxter (is an added weight. Referring to 
Fig. 12, 

Let V = the volume of displacement before the free water 

enters the boat over the gunwale. 
Let V = the volume of added water. 
Let 6 =3 the vertical centre of gravity of added water. 
Let i = the moment of inertia of the free surface of the 

added water, about its longitudinal middle line. 




FiQ. 12. 



For small angles of heel the weight of the free water will act 
through the point m, where 

i 



bm == 



V 



Thus the centre of gravity of the boat virtually drops from a 
point 6 to G', so that 



(V + t;)GG' = vGm 



therefore 



V 



GG' =^^ ^, - Gm 

V + 1; 



If the surface of the internal fluid had been fixed the drop of G 
would have been 

V 



Y+v 



G6 



54 



SHIPS' BOATS 



and, therefore, the loss of metacentric height due to freedom of 
surface 

V , i 

\ -\-v V + V 



(G6 - Gm) 
bm 



This refers to the metacentric height of a vessel of volume 
V + v, therefore, the loss of stability at a small angle 




Fio. 13. 



(b) Consider the water as a loss of buoyancy. Referring to 
Fig. 13, 

Let V be the intact volume of a boat. 

Let B' be the centre of buoyancy of this intact volume. 

Find a point M' where B'M' = . 

Where I is the moment of inertia of the water-plane WL 
about its longitudinal middle line. 

Then M' would be the metacentre if the surface of the internal 
fluid were fixed, and the restoring moment at a small angle 0, 
would be 

V . GM' . e 



FORM, STABILITY, STRENGTH, AND CAPACITY 55 

Owing to the freedom of the surface, this exerts an upsetting 
couple 

ie 

and, therefore, if 6M is the virtual metacentric height, the 
restoring couple at is 

V . GM . = V . Gwe - ie 

therefore GM' - GM = ^ 

In the first method (a) we are dealing with the change in the 
metacentric height in the volume Y -{-v, whereas in the second 
method (6) we are dealing with a change in the metacentric height 
in the volume V. In each case the loss in the initial stability 
couple is 

iS 

(c) The silbject was also treated from quite a different stand- 
point and based upon the application of a theorem evolved by 
an eminent French naval architect and known as '* Leclert's 
Theorem," which is an expression for the radius of curvature of 
the curve of flotation. 

A curve of flotation is the locus of the centre of gravity of , 
the water-plane ; in other words, it is a surface generated by a 
line drawn through the various positions of the centre of gravity 
of the water-plane as the boat is inclined at a constant displace- 
ment. A property of this curve is that the water-line at any 
point is always a tangent to it. The value of the radius of 
curvature is given by 

^^ rfV 

where in Fig. 14 W'L' is a water-line parallel to and very near 
WL, cutting off a volume V + ^ and having I + rfl as its trans- 
verse moment of inertia. 

Let g^ be the centre of gravity of the small layer of buoyancy 
between \VL and W'L'. 

Let wl and w'l' be the water-line when the boat is inclined at 
a very small angle from the upright, and let ^' be the centre of 
gravity of the layer in this condition. 

In the upright position the buoyancy of the layer acts in a 
vertical direction through (p\ and in the inclined condition it 
acts in a vertical direction through g\ 

The two lines of action will meet at 0. 



56 



SHIPS' BOATS 



Then becomes the metacentre of the small layer of buoyancy. 

When the layer is very small g^ and g' become consecutive 
centres of flotation. Og^ and 0/ are then lines through consecu- 
tive centres of flotation, perpendicular to consecutive tangents 
to the curve of flotation. is therefore the centre of curvature 
of the curve of flotation so that " the centre of curvature of the 
curve of flotation is the metacentre of the small layer of buoyancy at 
the water-line'^ 

The practical value of these considerations can now be applied 
to the case of an ordinary open ship's boat. 

In Fig. 15 let G be the centre of gravity of a boat loaded with 
a number of persons seated on the side benches and thwarts. 



-wt — 



r 



__ [\ -.-."._-."".":;.. J5-V 

rr's— ■ T ^Ti ^— ^— 




FiQ. 14. 

Supposing a weight of moderate amount w is placed on the 
lower seats at P. 

Consider the stability at a small angle $. The placing of w 
on board causes a small laver of buovancy to be added at the 
water-line of displacement u\ 

Thus we have : W the weight of the boat acting vertically 
downwards through G and w the added weight acting vertically 
downwards through P. 

The buoyancy V is acting vertically upwards through M. The 
metacentre and the added layer of buoyancy rfV is acting 
vertically upwards through 0, the centre of curvature of the 
curve of flotation. 

The effect of adding a small weight at the position shown, 
will be a restoring couple of moment «/? X OP sin Q. 

(ci) In a fully-loaded lifeboat, owing to its wall-sidedness, in 



FORM, STABILITY, STRENGTH, AND CAPACITY 57 

the neighbourhood of the load water-line and the gunwale, d\ ia 
practically zero, so that 

which brings the actual position of in the water-line. 

(C2) In an open boat of Class I., floating in the Ught condition 

and having a sharp rise in the underwater form, -^ will be a 

large quantity and would be necessarily high, consequently 




Fio. 15. 



any weight placed on board below will increase the moment 
ol stability. 

(C3) If there is tumble-home in the vicinity of the load 
water-line and a small weight is added to the boat, R will become 
a negative quantity, because the moment of inertia of the water- 
plane decreases as V the volume of displacement increases. In 
this case the position of will be below the load water-line. 

Thus, in the case of (ci), if a weight is added above the water- 
line it will diminish the moment of stabiUty. 

If added at the water-line, there is no change in the moment 
of stability. 

If added below the water-line, the moment of stability Is 
increased. 



58 SfflPS' BOATS 

An interesting feature of this treatment of the subject is, 
that the position of may be below the centre of gravity of the 
boat, and by adding a moderate weight to the boat above O, 
but below 6, the effect will be to reduce the moment of stability, 
which contradicts the usual but mistaken theory, that the 
addition of a weight, if added below the centre of gravity, always 
has the necessary effect of increasing the stability. ThiB latter 
reasoning does not take into consideration that, with an increase 
of draught, the metacentre usually changes in position, and that 
the initial stability depends on the relative positions of the centre 
of gravity and the metacentre. 

Applying the same principle to the case of an open boat 
having a quantity of internal water with a free surface, let us 

ur 

r ■ \i 

L. f^ 



follow out the effect on the initial stability by continually adding 
to this internal water. 

Reference is made to Fig. 16. 

In the same way that was shown to be the metacentre of a 
small layer of buoyancy, so 0', the centre of curvature of the 
curve of the centres of gravity of the free surface of the internal 
fluid, can be shown to be the virtual centre of gravity for a small 
addition of fluid. 

Supposing a small weight of fluid w be added, then at any 
small inclination, it will act through 0' and the small addition 
of buoyancy will act through 0. 

The relative positions of and 0' will determine the effect 
on the moment of stability. 



FORM, STABILITY, STRENGTH, AND CAPACITY 59 

If 0' is below 0, the stability will be increased until, when the 
two points coincide, the initial stability is at its maximum. 

As previously explained, the position of in a loaded boat 
would be usually found in the L. W.L. Therefore, we arrive at the 
conclusion that the initial stability will be at its maximum when the 
level of the water inside the boat is the same as that on the outside. 

The study of geometrical stability has a great fascination to 
students of naval architecture, and the writer has been prompted 
to refer to the subject at greater length than was originally 
intended. It is considered, however, that the result of Mr. 
Cannon's investigations has a very direct bearing on one of the 
most important phases of the subject as it relates to ships' boats. 
The Uberty has therefore been t'aken to give more than an outUne 
reference to these deductions. 

The form of boats must be considered so as to obtain the 
greatest values for initial stability, but as already stated, it is 
just as essential to investigate the maximum range of stability, 
and the effect of internal water with a free surface, on the 
stability, of boats, at large angles of inclination. 

Stability at Large Angles of Inclination. — Referring to Fig. 17, 
let W'L' be the inclined water-line of the boat, w'V the level 

Vi\ur 




of the internal water at this inclination, and WL the water-line 
of the boat in the upright condition. 

B is the centre of buoyancy of the water in the uprigjht 
condition. 



60 SHIPS' BOATS 

6 is the centre of gravity of the boat with no free water. 
First assume the internal water to be solid. Then the C.6. 
of the boat and water is at G', so that 

( W + w)KG' = W . KG + w^ . K6 

W being the weight of the boat ; w being the weight of internal 
water. 

Then, if B is the centre of buoyancy at the water-line WL, 
and if KN is drawn parallel to WL, the value of the righting 
lever G'Z, is given by 

G'Z = KN - KG' sin 6 

When at this inclination, assume the water to become liquid 
again. It will then take up the position indicated by w'l\ Let 
b' be its C.G. in this condition. 

Draw Vr perpendicular to w'V and br parallel to w'V, 

Then a weight w has been transferred through a distance 
br parallel to G'Z. 

Hence the loss of G'Z due to this 

w - 

Xbr 



W + w 

If b'r cuts KN at n, then br=Kn — Kb sin 0, therefore the 
loss of G'Z due to freedom of surface 

^ (Kn - K6 sin 0) 



W + w 

Thus in order to obtain the GZ curve for internal free water, 
first determine the values of KN and Kn in terms of the dis- 
placement of the boat and weights of free water respectively at 
various angles of inclination, and plot these in the usual manner 
as cross curves of stability. 

Therefore the effect of internal water, having a free surface, 
on the value of a boat as a life-saving appliance, at moderate to 
large angles of inclination, is to considerably reduce the moment 
of statical stability. 

In pontoon lifeboats of Classes Ic, IIb, and lie, water taken 
over the gunwale on to the deck would have a greater effect on 
the metacentric height than in an open lifeboat, if it were not for 
the special provision made to meet the emergency by fitting 
non-return drain valves in the deck. The special feature in the 
design of these three types of boat is that when water is taken on 
board, it is almost immediately cleared by the relief valves, which 



I 



FORM, STABILITY, STRENGTH, jVND C.U'ACITY lil 

automatically dischargu. the surface wat«r on deck very rapidly 
through tubes titt«d between the deck and double akin, and at 
the same time prevent water cetuminf; through the tubes on deck. 
In the case of open lifeboats of Class&s Ia. IIb, and Ha, water 
taken on board over the gunwale from heavy seaa increase in 
volume unless proper means are provided for discharging the same. 
The wat«r thus taken on board is situated at a greater distance 
from the centre of gravity of the boat than in the case of the 
pontoon lifeboats, but it seems very essential that some better 
provision should be made in open boats, say over 20 ft. in length, 
than the usual baler, by fitting a small mechanical hand pump 
at each end of the boat, which could adequately cope with all 
reasonable emergencies. 

The absence of buoyancy air-cases in a boat of Class 111. 
seriously reduces its efficiency as a life-saving appliance in vessels 
engaged in the Foreign Trade, but one has also to consider that 
this type of boat is only carried in cargo vessels, where boat 
accommodation is provided for the total number of crew, on 
each side of the ship. However, this type of boat, owing to its 
handiness in management and quick facilities for laimching, is 
often used when the larger lifeboats are kept in their stowing 
chocks. 

A comparison of the various featiires connected with the 
three main claAses of ships' boats is given in Table XI. (p. 62), 

A full detailed specification must be submitted to the Board 
of Trade before construction takes place on boats of Classes lo, 
IIa, FIb, and lie, and when completed the various types of boats 
have to undergo stability and other tests before a recognised 
standard of construction and dimensions can be followed. A 
satisfactory condition of stability is, therefore, practically assured 
with these tj-pes of boats. 

In the case of open boats, if tlie various factors referred to, 
when discussing the question of form, are recognit5ed, a reasonable 
measure of stability is assured in everj' condition of service. 
These guiding factors, based on the results of stability tests, are 
given in a convenient form for the information of the boatbuilders, 
to prevent the necessity of woi'king out extended calculations. 

Investigations of the Departmental Committee on Boats and 
Davits. — Before the subject of stability is brought to a conclusion, 
reference will briefly be made to some of the investigations of the 
Departmental Committee on Boats and Davits, the Report of 
which is published by His Majesty's Stationery Office, and 
be purchased through any bookseller. 



1 



62 



SHIPS' BOATS 



TABLE XI. 

COMPABISON BETWEEN CLASSES OF BoATS, WITH FULL LOAD. 



Buoyancy . 



Stability (bul- 
warks intact) 



Stability (parti- 
ally swamped) 



Open lifeboat, Class 
Ia. 



Pontoon lifeboats, 
Classes lo, llB, and lie. 



Floats witb full load i Floats with full load 



when swamjied to 
gunwale. 



StabUity(fullof 
water and at 
point of foun- 
dering 



Possesses good in- 
itial stability. 

Range of stability 
to about 28° to 30^ 

Moderately stiff, 
and has stability 
until gunwale goes 
below water-level. 

(See Curve R in 
Fig. 20.) 

Possesses good in- 
itial stability. 

Range of stability 
depends on free- 
board; varies be- 
tween 16'' and 20°. 

Has righting mo- 
ment untilgunwalc 
goes below water- 
level. 

(See Curve R' in 
Fig. 20.) 

Possesses very little 
initial stability 
and practically no 
range. 

There is a chance* 
of righting if occu- 
pants " duck un- 
der." 



oven when bul- 
wark is le^kking 
and so long as the 
permanent struc- 
ture is intact. 

Range of stability 
toabout29°to32*. 

Stiff boat, and has 
stability until gun- 
wale goes below 
water-level. 

(See Curve T in 
Fig. 20.) 



Ts unstable in up- 
right position with | 
water on deck, but 
with good relief ! 
valves cannot re- 
main long partially 
swamped. j 

Has a small range 
of stability. i 

(See Curve S in 
Fig. 20.) I 



No stability until , 
water is spilled | 
over the gunwale, j 

There is a chance | 
of righting if occu- , 
pants are not| 
throwTi overboard 
belore the treeing 
valves clear the 
deck. 



Open lifeboat, Clabs 

IlA. 



Has sufficient buoy- 
ancy to floai) with 
full load, provided 
permanent struc- 
ture remains in- 
tact. 

Should have a range 
of stability to about 
28° to 32°, provided 
bulwarks remain 
intact. 

Has stability until 
gunwale eoes be- 
low water-level. 



Fairly good range 
of stability, de- 
pending on free- 
board and bul- 
warks remaining 
intact. 

Is stable in upright 
position. 

Water has to be 
baled out, same as 
Class Ia. 



Similar to Class Ia 
Lifeboats. 



This Committee was appointed to advise the Board of Trade, 
in the interest of safetv of life at sea, as to what are the most 
efficient arrangements for stowing and launching boats, and 
several other vital questions aflFecting life-sa\nng appliances. 

Arising out of the terms of reference, the Committee made 



(FORM, STABILITY, STKENCiTH, AND CAPACITY 63 
eertain inve^stigations into the question of capacity and stability 
of boats, and attached to their Repoit are a number of diagrams 
which show the results of test8 upon different forms of boats, in 
the light, loaded, and swamped cunditionu. 
It was rightly pointed out tliat several boats were tested 
afloat, with the intended number iif pci-aona on board, but these 
tests could only bo carried out in still water, which was not con- 
sidired sufBcient to determine the fitness of a boat to cany, 

I in a seaway, the allotted number of persotis. 
The investigations were continued in order to ascertain the 
measure of stability of each boat, and the influence of form 
upon capacity and stability. 
Five different open lifeboatt) of Class Ia were dealt with, four 
of them being the same dimensions, but each having a different 
characteristic in design. 
Two decked, and one partially decked, boats were utilised for 
the purpose of securing data for comparison. 
Reference is made to the comparative tests carried out on 
two of the open lifeboats, named herein as A and C, and only as 
they aSect the subject of initial stability and maximum righting 
moment. 

The dimensions were as follows : — 
Length, 28 ft., breadth, 8 ft. 6 in., and depth, 3 ft. 6 in. 
Coefficient of Form : — A= "694 and C = "65. Type " C " boat 
ssed a much sharper rise of floor than the Type " A " boat, 
1 the comparative half-midship sections are shown in Fig. 18. 
In order to ascertain the conditions which would give equal 
Lability to boats having the same dimensions, but of different 
libims, the alternatives of initial motacentric height and free- 
Kbo&rd were tried, but, ultimately, both were abandoned in favour 
W>f maximum righting moment as a measure, because reserve 
■.Inioyancy and freeboard are both factors which Influence the 
e of righting moments. 
A compaiison of certain particulars in the two f^^pes of boats 
B gtveu in Table XII. 

TABLE SII. 



^t»«lrflx»t 


DlDMOllOD*. 


Capacity Id cubic Iwt. 


Ccwffl<>Iant ol 


LxBxDx-B. 


Stirling'. Eule. 


(ono. 


|(a>HiA) . 


88-(J'x9-6'x3-6' 
2IC(l'x8-B'x3-5' 


BOO 


577 


■6H 
■65 



J 



SHIPS- BOATS 











Typeofbort. 


Utaplgoi- DnilEht 
mant !□ ftom bottom 
toni. ol kiisl. 


loi)irfl»el. 


FlMbOUd. 


"ffl?^ 


A («l lisht draught) . 
C (al light dnvi^ht) . 
A (at luad draught) . 
C (al I(M<1 draught) . 


2'23 
203 
5-3tt 
5-1(1 


1:9: 

I' Ill- 
s' 2i' 


r 10" 

2' tr 
2' r 


2' 01' 
I'BK 


6-18' 
34' 

1-or 

2-0' 



n board}. Load Dnugiil (50 [wnoiu oa I 



The metacentric dia^^ams have been drawn for each boat 
and are shown in Fig. 19, 

It must be borne in mind that the weight per person used 
during these tests was 140 lbs., as compared with 165 Iba, in 1 
accordance with the Life-saving A ppliancea Rules now in operation, 
but in view of the provbion of lower cross-seats in boats of recent 
wjnatruction, which lowers the centre of gravity and increases 
the metacentric height, the comparison will be useful and s 
ciently accurate to show the various factors which come into 
operation in a boat with variable conditions of loading and in- 
clination. 

In order to obtain the maximum righting moment the boats* 
were loaded with weights, equal to a specified number of persons 
at 140 lbs. per pereoQ. Weight'* were then moved from the 
middle line t« the gunwale, to produce inclination, and it waa 
found that in the "C'"' boat the upsetting moment gradually 
increased aa the additional weight was placed on board, until it 
reached a maximum, with weights equal to 55 pej-sons, of 2-61 ft.- 
tona. The maximum upsetting moment for the " A " boat was 
reached when weights equal to 50 persons had been added, 
giving '2'76 ft. -tons, and when additional weights were placed on 
board the stability moment decreased until with 56 persons on 
board it amounted to 2-69 ft. -tons. 

In the upright condition it will be noticed that the " A " boat 
possessed a greater metacentric heiglit when floating at tJie light 
wat«r-line than the " C " boat, but with the weight of 50 persons 
on board, the " C " boat has '33 ft. greater metacentric height 
than "A." 

When loaded with weights equal to 55 persons, the range of 
etabihty for tlie " A " boat waa 281° and that for the " C " 1 
was 27i°. 



FORM, STABILITY. STRENGTH, AND CAPACITY 65 




scALc or Tons D/spiAceMc/rr 



-1- -— -' — " 


// 


\ 


•..'iis^ 


// 


\ si!^' 




-^^ 


, ^^- 




l^' 


""'S;*- 




tr- 


"A" 




— — ^^ 1 


/ 


\ ^ 


— ^ 




,/ 


, s^^fff-E.?:i!< 


.-jLfMAiSMMfln: 


/' ^ 


....... ■) 




/^^ "•■■ 




^-ij<.«/.«ff.tirt*t. 


/ 



Fio. 19, 



66 



SHIPS" BOATS 



When loaded with weights equal to 50 persona, which approxi- 
mates nearer to the number carried under service conditions, the 
angle of maximum stabihty for the " A " boat was 29J° and that 
foE the " C " boat was 28°. 

In the loaded condition the " A " boat possessed SJ in. more 
freeboard than the " C " boat. 

A further experiment was undertaken to ascertain the qualities 
of the " A " boat when flooded with water, by withdrawing the 
plugs from the drain holes and allowing water to enter, until it 
found ite level with the water outside, when it was found that 
3'9 ton-s had been admitted. The plugs were re-inserted and 
ballast was added to 'the boat ef}ual to the full load and placed 
as nearly as possible at the centre of gravity of the persona to be 
carried. When G cwta. had been transferred from the centre line 
to the centre of the side seats, the boat heeled through an angle of 
14|°, and after another half-hundredweight had been shifted water 
flowed over the gunwale. The masimuni angle of stability was 
16° and in this position the righting lever was found to be 
V5 in., the righting moment just balancing the upsetting 
moment. 

In the unawamped condition it requbed 13'D cwts. to bring 
the gunwale to the level of the water outside the boat, and the 
righting lever was then C'i in. 

The difference in displacement at the load and hght draughts, 
for both the " A " and " C " boats, should be exactly the same, 
being the weight of the number of persons placed on board. 

Investigations were also made into the stability of decked 
and partially decked lifeboats in a similar way to that adopted 
for open lifeboats. The full lines of these boats and the low 
centre of gravity of their complement of persona, give them a 
high initial stability combined with a long range, provided that 
the collapsible bulwarks remain watertight. 

The centre of gravity of a loaded boat is considerably in- 
fluenced by persona sta-nding on the deck of a pontoon lifeboat. 
It is essential for persons to retain their'aeats in these types of 
boats. 

The details aasociat«l with the various designs of decked and 
partially decked boats are dealt with in Sections D and E of 
Part IV. 

StablU^ Curves.— A number of typical statical stabihty 
curves are shown in Fig. 20. 

For the purpose of comparison, it is necessary to plot the 
curves for the moment of stability at various angles of inclination 



I 



FORM, STABILITY, STRENGTH, AND CAPACITY 67 




!♦» 




lO 


o 


«n 


O 


n 


o 


«n 


10 


lO 


CM 


CM 


- 


" 


o 



— SMOjiooj SINBWOW 9NriH9IU — 



I FORM, STABILITY. STRENGTH, AND CAPACITY 
Kecently, the " all wood " type of collapsible bulwark lias 
beoti accopted for open boate of Olaos Ha, which it in cousidertxl 
iucreasea tlii; stability and general seaworthiness of this particular 
type of boat, and it is anticipated that the same dettign of bulwark 
will be brought forward by the boatbuildcrs for the pontoon 
daas of lifeboat. 
The great essential with tlie lattcsr type of boat, is to preserve 
a watertight permanent structure and possess a suiHcient number 
ol rehof valves to carry away very quickly all surface water on 
the deck. 
The pontoon lifeboat of Class Ic, with fixed bulwarks and 
suitabit) rehef valves, provides a strong and eiEcient life-saving 
itppljance, but up till the present date it has not found general 
favour owing to the difficulty of stowage. 

Stability Test. — In paragraph (1) of General Uule 5 of the 
|Lifo-8aving Appliances Rules, it states ; — 

" All boats shall be properly constructed and shall be of such 
" form and pro|K)i-tions that they ahall have ample stability iu a 
" seaway, and sufficient freeboard when loaded with their full 
" complement of persons and equipment. They shall be fitted 
" and arranged to the satisfaction of the Board of Trade." 

Cases have arisen where the dimensions and form of a lifeboat 

e such as to raise serious doubts as to their stabihty. The only 

■iray to satisfy one's judgment is Ut undei'take a stability test by 

llbading the boat with weights equal to the full number of persons 

iried, and then incline her. 

The weights are arranged so that their centres are 12 in. 

ibove the thwaitu, side benches, or lower Heats, and equally 

Edistributcd throughout the length of the boat. 

It, therefore, becomes necessary to support the weights by 
mber above the seats, so as to brmg their centres to the 12 
^ee, which is asauined to be tlie height of the centre of gravity 
! a person sitting above the thwart or scat. Haif-hundred- 
_ meif^tB are usually employed for the purpose, as they can be 
eaaily handled and are to he preferred tw bags of sand. The test 
shoidd be undertaken in still water to faciUt*it« the accuracy of 
the readings and the residts From the incliuatious. 
^^v The boat is trimmed fore and aft on a level keel and the 
^^^Beighte arranged to allow her to be upright for the initial reading. 
^^H Two men are usually left in the boat to adjust the weights. 
^^H The freeboard is taken in the upright condition. 
^^B Weighbi, of known amount, are then moved from one side 
^^n the boat to the other throu^ a dednite distance d, as shown 



70 



SHIPS' BOATS 



in Fig. 21, i.e. 2 to 4 or 1 to 3, the weights being arranged in a 
fore-and-aft direction, with sufficient space between, to allow this 
to be done. 

As each set of weights is moved the alteration to the freeboard 
is noted on both port and starboard sides. 

Inclinations are continued until the gunwale is brought in 
close proximity to the water-level. 

From the information thus obtained a stability curve can be 
plotted. 

The following particulars are necessary before the test takes 
place : — 

(a) The actual weight of the boat. 

(6) The total weight to be placed on board to represent the 




Fig. 21. 

full number of persons and equipment, deductions being made 
for the amount of timber used for supporting the weights, and 
for the two men in the boat adjusting the weights. 

(c) The density of the water ; as this affects the freeboard. 

(d) The boat must be quite clear of internal water, unless a 
comparative test is undertaken to ascertain the effect of internal 
free water on the stability. 

Inclining Experiment. — If we possess the lines of a boat we 
can calculate tlie position of the centre of buoyancy and the 
position of the metacentre, and the correct position of the centre 
of gravity and the metacentric height can also be obtained by 
moving known weights in the actual boat through a definite 
distance d (see Fig. 21). 



FORM, STABILITY, STRENGTH, AND CAPACITY 71 

A plumb-bob ia auBpcntled at tlm middle line from a batten 
secured in a suitable iioaition. 

A lower cross batten ia fixed between the tank cleading, at a 
distftQce I below the point of suspcnsitin of the plumb-bob. 

The known weights are moved from one aide t« the other 

through a distance d, and the movement of the plumb-bob, from 

the upright position on the lower cross batten.'viz, " a," is noted. 

The moved weif^ht is replaced in its original position, when 

the plumb-bob should return to the middle line. 

Weights of similar amount are moved to the opposite aide 
and the distance " a " is again noted. 

It is evident that when the boat is inclined ftom the upright 

[ position by the movement of weights on board, the centre of 

I gravity will also move out in the same direction of inclination, 

' and the boat will come to rest when the centre of buoyancy and 

' the centre of f;ravity are in the same vertical line. For small 

angles of heel, the intersection of the vertical line in the inclined 

condition with the vertical line in the upright condition, will 

give the position of the nietacentre. 

If the angle of inclination ia 6. 

tan 6 
P,,. "Xd 

FtiKrfore ™ = w'^9 

If a = the distance the plumb-bob has moved along the 
lower batten, 
and I =^ length of plumb-bob from point of suspension to upper 
edge of lower batten, 

l.ihea tand=<^ 

Kbo that we arrive at an expreaaion from which the metacentric 
meigfat can be obtained, viz, : — 

VVx? 



J 



I 



72 SHIPS' BOATS . 

AHw iTmin jr that the wei^t o{ a boat b 116 cwta. : iveight iif 
ballast moved = d cvfta. ; diataace through which ballatit is 
moved = 6'0 ft. ; length of " f " = 30 ft. ; travel of plumb-bob 
"(i"=5m. (■42'); 

.1. r.M 6 Xli 6x6x3 



The position of the nietaceutre above the centre of buoyancy 
has already been calculated and setting down 2'22 feet below 
M we find the position of the centre of gravity of the loaded boat. 

Students ai-e referred ti> an interesting treatment of the 
question of stability of Self-righting Lifeboats, by Mr. E. L. 
Attwood, O.B.E., R.CN.C, in hia text-book on " Theoretical 
Naval Architecture." 

Reference to dynamical stability is made in Part Vll., 
Section B, in conjunction with '"Siiil Areaa and the Effect of 
Wind Pressure." 

The subject of stability has been treated at some length, the 
object of which is to impress upon boatbuildera and other readers 
the necessity of taking into consideration all the factors which 
have such an important bearing on the general design and 
structure of a ship's boat. 

It is therefore suggested that, if a little more careful thought 
and attention were given to the practical application of these 
principles, the efficiency of the life-saving equipment of our 
merchant vessels would be considerably increased. 

STRENGTH. 

The essential feature of ships' boats is to save life when it 
becomes necessary to " abandon ship." 

The greatest stresses a boat will probably have to meet with 
will be encountered when she is being lowered into the water, 
and not when she ia actually waterbome. 

The scantlings of all boats, which form part of the statutory 
equipment of a vessel, are designed on the assumption that the 
boats can be lowered in safety, with the fuU load, from the davita 
into the water. 

The details of the scheme of scautliijgs for wooden boats of 
Classes Ia, 1b, and HI, have, therefore, been drawn up, having in 
view the enormous stresses to which the boats may be subject«d. 

Combination of Frame, — The first provision is to secure a 



FORM, STABILITY, STRENGTH, AND CAPACITY 73 

Eaiiio strong enituj^li to aujjport tlie heavy weight of peitMJiis 
*rheii ttie boat is suspetulcd by the falla from the davit head. 

Special atteQtioa must be given to the method of aeciu-iiig 
Ite combintttious of keel, hog-piece, keelson, stem, stempOBt, 
Faprons, and deadwooda. 

With the exception of the hog-pioce, which is fastened to the 

keel with long brass screws, the whole of the combinatioDs 

referred to must be adequately scarphed together and secured 

Iwith properly clenched bo!t«, or, preferably, nut and screw bolts, 

laviag their points clenched over the heads of the nuts. 

The deadwo'jds and aprons are moulded to a size that will 

Inw the hooded ends of the planking being secured with a 

1 double row of fastenings, and the deadwoods should be sided 

Mfo as to provide a full faying suifacc for the garboard strake 

Old the strake immediately above the garboard. 

The ends of the timbers should be notched into the deadwood. 

The keelson is littcd to run tlie whole length of the boat, 

I^Karpbing with or lapping over the deadwoods so that the lilting 

hook keel boltfi grip the keelson, deadwood and keel, whether 

the boat is lifted in ordinary radial davits oi at the ends, as in the 

Weltn standard type of davit. 

The whole of the combinations and tbeit securities must be 
80 ananged that each separate portion takes its fair share of the 



In order that the stem and aternpost may he eSiciently 

bound together at the scarph, the full thickness of the keel is 

inaint£ned throughout ita leugtli, so that the bearding of the 

B«tem or sternpost does not comnieace until the upper edge of 

■he keel, at least, is reached. 

Timbers,— Havmg provided a strong backbone for the boat, 

)uld be given to the timbers and planking. 
It was quite a general practice at one time, to space the timbers 
from 8 to 9 in, apart, in the open type of boats, and sometimes 
at a greater distance. Instructions now issued, make it necessary 
~* limit the spacing to 6 in., centre to centre. 

The writer is fulfly aware of the heavy scantlings of the timbers, 
tat tiie sizes are based upon the great stresses to which the boats 
MB subjected. Timbers should extend from gunwale to gunwale 
and attention should be given to ascertain that no halt timbers 
exist, except at the ends of the boat, before the keelson is pliu'ed 

t position. 
Planking. — The planking is worked to a minimum breadth 
5J in. over-all, except the garboard and adjacent strakes. 






at a 



74 



SinPS' BOATS 



The narrowest strakes should be situated at the bilge. It is 
considered essential that the gaiboard, bilge, and binding strakes 
should be kept slightly thicker than the remaining strakes of 
planking. 

A weak portion of the ordinary open type o£ boat is situated 
at the bilge, due to the soleing away'of the plank edges. The 
quicker the bilge, the weaker becomes the section ; hence it ia 
advisable to work an "easy bilge" for the planking. Narrow 
planks lend themselves better to the operation of soleing. In 
any case there is a weakness at this particular part and it becomes 
necessary to fit, fore and aft, in one length, a bilge stringer of 
the same scantlings as the rising, but througli-fastened and 
clenched only at alternate timbers. If bilge planks were limited 
m breadth to 4J in., it is considered it would be an advantage to 
the boat. 

Stringers. — The bilge stringer in boats over 24 ft. in length 
ticarph with the lower breasthook. 

The rising is fitted to give adequate support to the ends of 
the thwarts, and if the thwarts are checked into the rising, the 
latter should be increased in depth accordingly. 

The sides of the boat are well held together with a minimum 
number of thwarts, but it ia considered generally by the boat- 
builders, that all boats should be fitted with double knees, 
especially at the thwarts in way of the gripes. 

Side benches, instead of scarphing with the thwarts, are 
continued in as long lengths as possible above the thwarts and 
well secured by heavy screws to the thwarts, or preferably" bolts, 
where single knees only are fitted. 

The upper etrake, rubber and gimwale, provide a very 
efficient girder to resist the sudden stresses which oome 
upon the boat when being lowered from a great height, provided 
an efficieJit connection is made between the , timbers and the 
gunwale. 

Gunwale. — Boatbuilders are unanimous in their opinion that 
the most efficient ^zunwale is the " box " type. 

It is the writer's confirmed opinion that when boats are 
lowered from davits situated a great distance above the water, 
where there ia every chance for the boat to swing and come in 
violent contact with the ship's aide, the ordinary solid gunwale, 
in these circumstances, is a source of danger, arising from its 
inadequate coimoction with the timbers. There is plenty of 
evidence from practical experience to support this opinion. 

The box gunwale is infinitely stronger, more resilient to sudden 



FORM, STABILITY, STRENGTH, AND CAPACITY 75 

blows and distributes the stresses received through the timbers 
to which it is connected. 

Lifting-Hooks. — The position of the lifting-hooks has a material 
effect on the question of the stresses 'coming on the boat. 
The ideal position would be at the quarter-length of boat, where 
the supporting chocks are now fitted, but this does not suit the 
radial type of davit, and the hooks would interfere with the 
seating accommodation. The nearer the lifting-hooks are fitted 
to the ends of the boat the greater will be the stress on the boat 
when hanging from the davits. It is, therefore, necessary in 
the case of those particular davits where the lifting-hooks are 
fitted from 15 to 18 in. from the front of the stem or back 
of stempost, to provide special strengthening at the ends. 

These various points are referred to in greater detail in the 
general description of the construction of the different types of 
boats. 

To provide for the " unusual circumstance " when passengers 
may probably be in a condition of panic, and the crew have 
considerable difficulty to control the lowering of the boats, it is 
essential to maintain a high factor of safety in the strength 
of the boats and in all the details connected with the launching 
appliances. 

Ships' officers have already confirmed the opinion of the 
writer, that the type of lifeboat now placed on merchant vessels 
is a great improvement on the old standard of construction, and 
that expression of opinion is base^ on the results of actual ex- 
perience, when vessels under their command have been torpedoed. 

Supposing it became necessary to ascertain the amount of 
stress exerted on the gunwale of an open boat of Class Ia (clinker 
built) when suspended from ordinary radial davits and having 
the full number of persons on board, the calculation involved 
is arranged in the following order : — 

As an example take a Ufeboat with dimensions : — 

280' X 8-5' X 3-5' 



The scantlings of the material running fore and aft are : — 


Keel . . . 5^'' X 3'' Rock ebn. 


Hog-piece . . SJ'' x 1" ., „ 


Keelson . . 6^ X 3}" „ 


(scored over 
timbers). 


Bilge 8triii(^^cr V X J" Pitch pine. 


Rising . . . V XV 


Side benches IV X IJ"' „ 





76 SHIPS' BOATS 

Rubber . 1^" X li" Rock elm. 
Planking . . . . f' Larch. 
Upper strake Dj'' X f Teak. 
Solid gunwale 2|'' X 2^" Rock elm. 
Box gunwale I'' X 3J'' „ „ 
Depth of thwart below gunwale = 11 in. 



Estitnated WeigJUs. 

Cwt8. 

Boat, including buoyancy air-ca«es = 35*7 

Equipment ==6*5 

Persons (50 in number) . . . = 73*7 

Total load .... 1159 

A^uming the lifting-hooks to be situated 3 ft. from the 
stem and sternpost rabbeta, then the distance between the hooks 
will be 22 ft. 

The bending moment of a beam evenly loaded and supported 

at the ends, is —tt-. 

o 

The bending moment of a beam with load at middle of length 

and supported at ends, is -j- . 

Therefore assume bending moment of loaded boat under 

conditions of support as ^. # 

u 

W = tot^l weight of boat and persons. 
L = distance between lifting hooks. 

Therefore BM = ^ ^""''[^ ^^"^ = 425 f r.-cwts. 

To calculate the compression on the gunwale we use the 
followiui' formula : — 



'r> 



My 

/; represents the intensity of the stress exerted on the gunwale 
due to bending, at any point of the section, at a distance ?/ from 
the Neutral Axis. 

M is the Bending Moment, and 

I is the Moment of Inertia of the section about its Neutral 



FORM, STABILITY, STRENGTH, AND CAPACITY 77 



The first operation is to find the Neutral Axis and moment of 
inertia of the midship section. 

SnUkHE 




B/LGC SrPftNG€R 


^jnjureLawt 


^^-^MiNG 





Fio. 22. 



Assume Neutral Axis as 2 ft. 3 in. below gunwale, and life- 
boat fitted with solid gunwale. 



Rbfsrenoe is made to Fio. 22. 



Item. 



Section. 



Area 
in sq. 
inohee. 

A. 



Distance in 

feet from 

assumed 

N.A. 



Moment 



At/ 



MofI 

abont 

aasomed 

ir.A. 

Air- 



( 



M of I of seotion about 

AJb* 

its own axis « 15- 



Qunwale 
Top stiake . 
Si& planking 
Side seats 
Rubber . 
Rising 



lUma obovt assumed Neutral Axis, 



2J''x2}' 
bV X r 

2irxr+A 



th 



\Yx\v 



6-63 
3-94 
14*96 
16-75 
2-26 
4-00 



215 
2*04 
0-90 
1-37 
1-76 
105 



12*08 
I 8-04 
, 13-46 
I 21-58 
; 3-94 
4-20 



I. 



25-97 I 
16-40 
12-11 
29*56 

6-90 

4*41 



Ax 14*95 Xl-8««4-a4 



Total M above axis 63*30 j 
Items below assumed Neutral Axis. 



Bilge planking . 18*xr+A*' 12-37, 

Bottom planking 33*'xr+ A*** 22-69 

Kaelbalf . .' 6J'xir 

Hog half rx2r 

Keelson half 4^x1^ 

Bilgp stringer . 4' X J' 

« 

Total sectional an>a 103*20 



8-26 
2*63 

7-74 
3-00 



0-5 
1*0 
1-5 
1-2 
0-9 
0*5 

Total M 
below axis 



I 



6*19 
22-69 
12-38 
3*16 
6-97 
1*50 



8*10 i^X 12*37 X*8*«>*66 
22*69 
18*57 

3-79 

6-27 

0-75 



1 52*89 150*52 



Moment above axis 63*30 
Difference 10-41 



= -10 



Distance of Neutral Axis( lOjU^ .^ 
above Assumed Axis j"" 103-20 

Assumed N. A. below gunwale =2-25 



Actual N.A. below gunwale =2-16 

NoTB. — i^n*'' added to^planking to allow for landings. 



-f4-70 

Ay s- 150-52 

Moment of Inertial ___,--. „ 
about Assumed Axis f oo - ss 
(Correction for C.G.) 10320 x -1*= 1-03 

M of I about actual \ ,,^ .1 
Neutral Axis |=154 l» 

For both sides 2 

308-38 



78 SHIPS' BOATS 

I = moment of inertia of section ' = 308*38. 

y => distance of neutral axis below gunwale = 2*15 ft. 
M =j bending moment => 425 ft.-cwts. 

p = stress on gunwale, in cwts. per sq. inch. • 

My 

_ 425 X 2-15 

"~ 308-38 

=> 2*96 cwts. per sq. in. 

Sectional area of gunwale . . . = 5*63 sq. in. 
Total compressive stress on gunwale = 5-63 X 2*96 

= 16-68 cwts. 

If we consider the gunwale as a pillar held firmly at the 
thwarts spaced 4 ft. 2 in. apart, the strength of the gimwale is 
obtained by Euler's formula as follows : — 

2 EI 



a) 



p = greatest load consistent with safety. 

E => modulus of elasticity = 700 tons per sq. in. 

I = moment of inertia =. ^ -— -^=i 2*93 

12 

I = length in inches. 

Q 1^2 v/ 700x2-93 
7) = 3142 x-^ — ^^ 
^ 25 X 25 

= 32-34 tons. 

CAPACITY. 

There appears to be doubt in the minds of shipbuilders and 
others as to where the dimensions of an open boat of Class I. are 
measured. The extreme length of the boat is taken from the 
fore side of the stem-head, to the after side of the stempost-head, 
or in other words it is the " over-all " length. 

The external 'capacity length is taken from the intersection of 
the outside of the planking with the stem, to the corresponding 
point at the stempost, ot, in the case of a square-stemed boat, 
to the after side of the transom. This is the length used in 
conjimction with the formula for obtaining the capacity of a 
boat (LxBxDxO-6) and is the recognised length. When we 
refer to a boat as being 28 feet in length, it is the external capacity 
U fiiftt 18 meant and not the extreme length. 



I 



FORM, STABILITY, STRENGTH, AND CAPACITY 79 

Shipbuilders should bo careful, therelore, in sending lo the 
boatbuildera the position of the lifting-hooks, tii distinctly state 
where they are to be fitt«d in relation to the outside of plank 
rabbet, or to the stem and stempost-heads. In addition, the 
distance between the hooks should be j^iven. Inconvenience 
will often be avoided if attention is directed to this point. 

The internal capacity length ia taken from the inside of the 
planking or platinf; at the stem to the corresponding point at 
the stempost, and in the case of a sqiiare-stemed boat, the 
length is measuretl to the inside of the transom. This length is 
only used when Stirling's Rule is being employed for asccrt«ining 
correctly the internal cubic capacity of a boat. 

The breadth of a boat is taken from the outside of the planking 
at the point where the breadth of the boat in the greatest. This 
dimension is usually measured from the outaideof the upper strakes. 
The breadths used with Stirling's Rule arc taken from the 
inside of the planking. Shipbuilders should keep in mind when 
arrangibg the outreach of davits, to take into account the 
thickness of the rubbers, or rope fenders if such are fitted, These 
items project beyond the maximum recognised breadth. 

The recognised deplh is the distance measured amidships, 
between the inside surface of the planking at the keel, to the level 
of the top of gimwale. 

The number of persons that can be allotted to an open boat 
of Class I. depends, in the first place, on the cubic capacity, and 
secondly, whether proper seating arrangements can be made for 
tiie number ascertained by dividing the cubic capacity by the 
correct unit of capacity, provided, of course, that the dimensione 
and form are suitable. 

The cubic capacity of motor boats, and deck areas of pontoon 
boats and of open boataof Class 1 1, are separately dealt with under 
i^ar own particular section. 

The various dimensions before mentioned are illustrated in 
lllg. 23. 

I The total volume of the buoyancy air-casea ia to be not less 
Itiian one-tenth of the cubic capaciti/ of all open boats of Class Ia. 
~ Atbuilders need to keep this provision in mind. The volume 
f€i air-cases is not calculated upon the number of person.'} carried, 
kand it is usual for tinsmiths to add a percentage to the cubic 
t given for the number of persons carried, calculated by the 
lL>jBxDx06 Rule. As an example, a Class Ia open boat, 
■wi^ dimensions 280'x8'5'x35' giving 50 persons by the rule 
Vsientioned, would probably have a cubic capacity between 540 



SHIPS' BOATS 




EXTREME LENOTM - 



FORM, STABILITY, STRENGTH, AND CAPACITY SI 

auii 560 ft., if measured by Stirliiifj'a Rule, and in that caau the 
buoyancy air-cascu wuuld have to be 54 or 56 cub. ft. and not 
50 cub. ft. 

Full detaibi are given in the Rules for Life-siiviny Appliances, 
am to the correct method of obtaining the cubic capacity of open 
boats of Class I., which are an follows :— 

" The cubic capacity shall be determined by the following 
■' formula :— 

■' Capacity = (4A + 2B + ■IC) 

" I denotes the length of the boat in feet, fi'om the iutiidc of 
" the pbnking or plating at the stem, to the corresponding point 
'• at the uternpost ; in the cajse of a boat with a square stem the 
" length is measured to the inside of the transom. 

" A, B, C denote respectively the areas of the cross-sections at 
' the quarter length forward, amidships, and the quarter length 
' aft, which correspond to the three point* obtained by dividing 
" I into four equal parts (tlie areas corresponding to the two ends 
" of the boat are considered negUgible). 

■■ The areas A, B, C ahalt be deemed to be given in square feet 
" by the successive application of the following formula to each of 
" the three croas-aectiona : — 

f, 
" Area = 



" h denotes the dejAk measured in feet inside the planking 
"or plating from the kee! to the level of the gunwale, or, in 
" certain cases, to a lower level as determined hereafter. 

" a, b, c, d, e, denote the horizontal breadths of the boat, 
'* measured in feet, to the inside of the planking at the upper and 
" lower points of the depth and at the throe points obtained by 
" dividing A mto four equal parta (n and e being the breadths at 
" the extreme pointa and c at the middle point, of h). 

" If the sheer of the gunwale, measured at the two points 
'■ situated ut a quarter of the length of the boat from the ends, 
" exceeds 1 per cent, of the length of the boat, the depth 
" employed in calculating the area of the cross-sections A or 
"shall be deemed to be the depth amidships plus 1 per cent, of 
" the length of the boat." 

There are certain limitations to the depth used for calcu- 
lating the capacity of an open boat of Class 1a, but these would 
be unnecessary if the dimensions of boats indicated in Table VII. 



82 



SHIPS' BOATS 



wave worked U*, ua anything approaciiiuf' io per cent, nf the 
breadth for the depth, is considered by practical boatbiiilders 
to be unsuitable for a rowing boat. The limitatiooB referred 
to are as followa : — 

(a) " If the depth of the boat amidshipM exceeds 45 per cent. 
•' of the breadth, the depth employed in calciUatiag the area of 
■■ the midKhip cross-section B, shall be deemed to be equal to 45 per 
" cent, of the breadth, and the depth employed in calculating the 
" areas of the quarter length sections A and C, shall be obtained by 
" increasing this last figure by an amount equal to 1 per cent, of 
■■ the length of the boat, provided that in no case shall the depths 
" employed in the calculation exceed the actual depths at these 
" points. 

(b) " If the depth of the boat is greater than 4 feet, the number 
" of pereona given by the apphcation of these General Rules, shall 
■' be reduced in proportion to the ratio of 4 feet to the actual 
■' depth, until the boat has been tested afloat with that number 
" of persons on board, all wearing life jackets, and the test has 
" proved aatiafactory," 

The details in calculating the internal cubic capacity of an 
open boat of Olaaa Ja with dimensions 28-0'x8-i3'x3'5' are 
shown on p. 83, and it will be seen that if twenty boats in one 
boat-yard are to be measured by Stirling's Rule and calculations 
made from the results, the operation is one which entaila a 
great deal of labour. Life ia too short for this rule to be con- 
stantly in operation. If a coofiicient of form ia recognised and 
check dimensions be applied tt> the forward and after quarter 
cross-sections to enable the boatbuilders to make suitable moulds, 
there would be very few occasions when it would become neces- 
sary to use the exact method of obtaining the capacity. The 
following rule would, therefore, become operative, viz : — 

(c) " The cubic capacity of a boat may be assumed to be the 
" product of the length, the breadth, and the depth, umltiplied by 
■' 06 in cases where it is clear that this formula does not give a 
"greater capacity than that obtained by the above method (at 
" (o) and {b}). The dimeusioua shall then be measured in the 
" following manner : — 

" Length : From the intersection of the outside of the phinking 
" with the stem to the corresponding point at the stempoat, or, 
"in the case of a square-steraed boat, to the after side of the 
" transom. 

" Breadth : From the outside of the planking at the point 
" whei-e the breadth of the boat is greatest. 



fORM, STABILITY, STRENGTH, AND CAPACaTY 83 

" Depth : Amidships, inside the planking from the keel to 
" the level of the gunwale, but the depth used in calculating the 
" cubic capacity may not in any case exceed 45 per cent, of the 
" breadth, 

" In all cases the shipowner shall have the right to require 
" that the cubic capacity of the boat shall be determined by 
" the exact measurement." 

When referring to the specimen calculation of the capacity 
of an open boat by Stirling's Rule, attention should be directed 
to the section of Fig. 23. 

Cil^JULATIUN IfOR InTKHNAL CAPACITlf OF AN OfBM BoAI Q¥ ClASS 1. 

Uiuipuaions : 28-0' x 8*5' x 3-5'. 



:i3-32 

ltl'58 
3012 



7-70 
7-40 

7-05 



Intenial i»[>iicitv !i-iiBt]i— ^71 



Cu<llit:icttt uf /orm^ ^"liSU 
K limber of ih'ihodh by cii[jBcity =5fi 
JiumU'r uf pcrsoua limited byt _^„, 

a'aliiig arningomtnts / ^ 



DIH3J3t i 
Total intcmnl CB]iftcity = Sfll cub. (t. 



SECTION A.~TiMBEH : CONVERSION, SEASONING, 
DISEASES, SELECTION, STKENUTH, ETC. 

TuE first British writer to f^ive th« benefit (if his invcHtigationB 
by publishing a treatise on the subject of " Timber '" was in tha 
year 1664 ; and since that date a great wcaltli of information 
has been collected, as a result of experimental and research work, 
by many eminent and distinguished experts. 

In the days of wooden shipbuilding, the subject of timber 
was one that attracted the attention of some of the best scientists 
of that period, particularly with reference tti its treatment in 
order to prevent decay, and to increase the lasting qualities ol 
a vessel. 

Of recent years valuable help has been given to shipbuilders 
and other traders associated with the use of wood, by the 
publication of text^hooks containing the results of the practical 
experience of such authors as Professor Marshall Ward, D.Sc., 
Mr. T. D. Laslett, Mr. J. R. Baterden, and, more recently, Mr. 
Webster who has devoted his attention to British home-grown 
timber. 

If students wish to advance their knowlec^e oi the subject, 
they arc recommended to read the published works of these 
authors. 

It is not the intention of the writer, in the present section, 
to enter into any great detail on the physiolo^ of trees, but 
only to collect a few sahent features of the subject, combined 
with the result of some practical experience, which may help in 
the investigation of the best methods to be used in selecting, pre- 
serving, and working timber into the construction of ships' boats. 

As an Empire and a Nation the " Great War " has taught us 
many things, and the urgency of forestry development, as one of 
the problems in the national reconstruction scheme, is of the 
greatest importance. 

In proportion to its size Great Britain has less woodland than 



J 



TIMBER: CONVERSION, ETC. 

any otiier country in Europe with the exception of Portugal, 
and inipoT*6 more timber than any other country in the world. 

To increase our own national r€aourcefi and make this countrj 
independent of auch a volimie of imported timber, it isconsidBred bv 
experts that it wiU be neceasary to afforest at least 1,500,000 acrea. 

During the European War we felt the difficulty very acutely in 
not having sufficient seasoned material to meet one-twentieth of 
the demand. Substitutes have been found to meet the urgency, 
but the subject is one of the greatest importance for future 
consideration. 

Growth of Timber. — If we examine the cross-section of a 
balk of timber we see that it is made up of three distinct portions, 




viz. the pith at the centre of the tree, the heartwood. and the sap. 
The tree appears to be bound together in its structure by a 
number of layers nr anmial rings, which vary in thiekneaa. bein^ 
[ narrower at the centre and becoming wider towards the outer 
I surface. Each of these layers are made up of two distinct parte 
I (see Fig. 24), the lighter and larger being the spring-grown wood 
T and the darker being the autumn wood, the latter being much 
( harder than the former. 

We are thus able to approximate to the age of the tree by the 

I number of annual rings. A layer may vary in thickness owing 

I'to one portion of the tree having a better situation than the 

fother. Trees grown in high altitudes do not show such a distinct 

wntrast between the spring and autumn wood, but where there 

B rapid changes in the seasons, the contrast is magnified. In 

Ktropical countries the rings appear to nm into one another. 



I 



80 



SinPS' BOATS 



The thicknesfl of the annual ringa partly governs the c 
of timber into two distinct claasea, viz. hard and soft woods. 
All timber converted from trees which are cone bearing and 
have Hpikea instead of leaves, is of the soft wood class, being 
wider rinj^ed and quicker in growth. The slower growing trees 
which bear leaves, produce hard wood. Some of the so-called 
hard woods are found to be softer than the generally accepted 
" soft woods " and it is, therefore, eBsential in formulating 
specifications to distinctly name the particular specicB of timber, 
instead of using the general terra " haid wood." 

The lighter coloured portion of the timber is the sap and of 
least value for convei'sion, containing a greater quantity of 
moisture than the heart wood, and tlierefore more liable to the 
attacks of disease. 

The sap is the passage through which the tree derives its 
nutriment or sustenance, and if this is removed the tree will 
eventually die. In process of time the sap wood becomes heart 
wood. 

If we were able to examine verj- closely and minutely the 
structure of the section of a tree we should find that it appears 
to be made up of a number of long and narrow cells full of 
moisture, the shell varying in thicknesfl according to the hardness 
of the wood. The nearer to the pith or heart wood we examine, 
the less moisture we find, and the closer together become the 
cells. 

The nutriment is conveyed from the roots upwards through 
the passage cells of the sap wood to the leaves, and in their turn 
the leaves give off oxygen and take into themselves gaseous nutri- 
ment from the atmosphere. Thi-* passes through some peculiar 
process of solidification and returns through the bark, which 
causes it to expand and allows the more perfected sap to fill the 
cavity and become hardened. This operation thus produces a 
distinct layer <jf wood as indicating adefinite period of growth. 

Rimniug from the centre or pith in a radial direction at right 
angles to the longitudinal cells, arc very hard and thin cells 
called medullary rays (see Fig. 24), which serve to connect the 
various annual rings and keep open a passage for tlie conveyance 
of life to the centre portiim of the tree and which alao relievos to 
some extent the constant pressure from the contraction of the 
ringa or layers. Tlie medullary rays of uak are very noticeable 
and pnidnce a fine silky appearance when the timber is cut on the 
" Quarter Sawing " methinl. 

a.— Trees should be felled when they arrive at a 



I 



TIMBER: CONVERSION. ETC. 



87 



^^t mature age, that is to say, when the largest poition of tlie tree is 
^^K lieart wood and the sap has become solidiiied and elastic, the tree 
^^Tis then in tts strongest and moat suitable condition lor conversion. 
^B If the tree is allowed to stand beyond this condition of maturity 
^F the hsart wood becomes brittle and loses it6 elasticity and strength, 
and being in a condition of " decline " it becomes exposed to the 
effects of decay. 

On the other hand, if the tree is feJled before this condition of 
maturity, we find that it contains a large portion of sap wood and 
consequently is full of moisture. It is, therefore, not so durable, 
strong, or tough, and the timber becomes more susceptible to dry 

Iiot and other diseases. 
The condition of maturity also depends upon wliether the 
tree is of hard or soft wood. The rapid-lowing trees, whose 
annual rings are wider apart, are felled before those of a slower 
growing nature with armual rings much closer together. 
There are two periods in the year when the trees are in a 
condition of vegetation, viz. the spring and the autumn, more 
eepecially during the former season when the bulk of the new 
wood is formed, and it is, therefore, very essential that the tree 
should be felled during the period of rest in midflummer or winter, 
preferably during the latter season after the autumn growth has 
taken place and which is of more value than the spring sap wood. 
It used to be quite a common practice to strip the bark oJT 
^H tJie trees in the spring and allow them to stand in this condition 
^K for twelve months, the reason given for such procedure being that 
^B the sap was hardened and t)ie strength of the tree increased. 
^H The bark of the oak tree is of great commercial value and is 
^H'UBually stripped in the spring, being more easily detached at that 
^^Kperiod of the year. 

^^B During the present European war the demand for home- 
^^ftjgrown timber was greater than the supply, with the residt that 
^^Ktimber was felled at all seasons of the year, greatly to the 
^^R detriment of the lasting quahties of the wood. 

There are certain recognised terms applied to timber in its 
various stages of conversion. 

TiitAer is the name applied to the tnmk or body of the tree 
aft«r it has reached a diameter of eight inches. The loff is the 
trunk of the tree with its hark and branches removed ; and when 
this is trimmed and sawn into square sections it is then termed a 

Ibaik and from the balk are produced planhs and deals, the former 
bnng from two to six inches in thickness and from eleven inches 
Id widt^, the latter varying in thickness from two to four inches 



88 



SHIPS' BOATS 



and nine incliea wide. Boards are thin pieces of timber of any 
width. 

Loga are usually seasoned in the open and then cut into 
planks. Two methods are adopted, the usual practice in the 
boat yard is the easier one and is termed " hastard samng " 
{Fig. 25), i.e. cutting the log longitudinally into planks, and 
although this is considered the more economical for conversion 
the quahty of the planlra will vary considerably, those which are 
cut at the centre of the log at right angles to the medullary rays 
will have very little sap, but the planks cut near the outer edges 
will contain a large proportion of sap. 

Quarter samw) (Fig. 26) divides the log into four parts and 
cuts the planka from each individual part at right anglea to the 
annual rings. This process enables one to obtain the minimum 





amount of sap, and as the medullary rays radiate from the centre 
of the log and at right angles to the rings, the full advantage of 
the silky grain of oak is obtained. This method is often adopted 
for cabinet maker's work, but is not often reported to in cutting 
material for boatbuilding. 

Seasoning. — The purpose of seasoning timber b to extract 
the moisture from the cells. As already explained the shell of 
the cells of all hard wood is thicket than those of the soft wood 
and more easily split if dried with rapidity, not being able to 
adjust itself to the new conditions. Timber of the character 
of oak and elm, therefore, needs slower seasoning to prevent 
splitting. 

During the process of seasoning, timber loses weight con- 
siderably but increases in strength. Stresses are constantly in 
operation tending to distort and injure the fibre by contracting 
the longitudinal cells and medullary rays, A\Tiece balks or 



TIMBER: CONVERSION, ETC. 89 

planka of hard wood are exposed at the ends they naturally dry 
quicker at these positions and the distortion is more noticeable. 

The loss of weight due to seaaoniug, in some of the moat 
important woods used in brtatbnilding, is as follows : — 

Red pine 12-25 per cent. 

Yellow pine 18-27 

Larch 18-27 

British oak 16-30 

Elm 40 

Mahogany 16-2ri 

One of the moat important features in connection with the 
construction of ships' boats is the question of the satisfactory 
se^aaoning of timber. 

During the war the boatbuilders were handicapped through 
the necessity of using the only available supply of timber, whieh 
was home-grown and nished on the market to meet the heavy 
demand, but the material was quite out of condition to suit 
the requiremente, 

During normal times the majority of the builders are inclined 
to work on the " hand to mouth " principle, without anticipating 
events and keeping a good stock of timber in store, well pinned 
down for seasoning. It is a policy that does not eventually pay. 
The most successful builder is the man who makes his plans for 
the stocking of the timber yard twelve months ahead of his 
requirements, to enable him to have at his disposal material 
which has been well seasoned. 

Ab soon as the planks are cut from the log or balk, they should 
be -placfd under cover, on a dry foundation, protected from damp- 
ness and wind, but allowed a free circulation or current of air. 
To obtain the maximum amount of durability, toughness, and 
elasticity, it is eaaontial that the timber should be seasoned 
slowly. 

Hot air apphed under preaaure is sometimes resorted to in 
order to shorten the period of seasoning, and although some 
experts maintain that steamed timber is not so hable to shrink 
and ia less susceptible to dry rot, yet it possesses the disadvantage 
of decreasing the strength of the wood, and produces a hard veneer 
on the surface which does not readily permit of the thorough 
evaporation of the internal juices, 

Water seasoning is resorted to for shipbuilding purposes, but 
the balks must be totally immersed. Tlie internal juices of the 
aap which are more inclined to decay, are supposed to be more 



i 



90 SHIPS' BOATS 

efficifintly remnvinl by tliis method tlmn by adopting the ordtnaiy.! 
precautions. 

Detects seen alter Conversion. — During the process of ^ 
Beaaonin^, defects will bec-ome magiiified. The preseHce of cwp 
shakes (Fij;, 27} are attributed to the result of sudden chaugea of 
atmosphere, producing a detrimental effect on the sap and 
checldng the normal growth ; they usuall} take the same shape 
as the annual rings, 

Star and Heart Shakes (Fig. 28) generally occur at the ends of 
a log and are the results of the timber drying quicker at the 
exposed extremities. Where trees have been growing on loose 
soil the timber at its centre appears to be split up with shakes 
and cleft«. Material in this condition i.s said to be " Quggy.'' 

Rind Galls (Fig. 29) are produced through injuries to the tree 
by broken branches which, on being exposed to the atmosphe 




become rotten. The injury ia subsequently covered up by the 
natural growth of the tree. 

Resin (rails arc very difficult to discover until the timber b 
cut up into planks ; they often occur in larch. No mercy should 
be shown to the plajika in which these galls are discovered and they 
should be immediately removed from the boat. The effect of 
the sun quickly opens out the defect, and caulking a thread of 
cotton intji the cavity only accentuates the trouble. 

Black Knots. — One cannot expect to secure larch without 
knots, and the inspector must use his own judgment in dealing 
with the^e. Sometimes a good doubling is of more value than 
removing the plank. 

Upsrls are defects which produce a separation in the grain of 
the wood, 

Faxiness particularly applipji to nal( which is grown on 
awanipy ground ; it gives a reddish colour to the wood near the 
heart, which ia clejir evidence of approaching decay. 

Worm Holes, — Thcae very often occur in teak and mahogany. 



I 



TIMBER: CONVERSION, ETC. 



91 



Thoae in the former material are very quickly discovered, but in 
mahogany a very close inspection is needed to locate them ; 
they are usually about the size ()f ao ordinary pin head. 

Disease. ^The sap which rises through tho tree contams an 
acid and if the flow is checked by atmospheric effect or is left to 
itself, it quickly ferments and in the ripe condition generally 
becomes infected by any fungus growth. This growth usually 
appears at the base of the tree, feeding on the vegetable 
substance of the sap, pieroinj^ the cells, and eventually turning 
the timber into the condition of a sponge. Other trees in the 
immediate vicinity of the infected timber very quickly become 
contaminated. 

Dry aiid Wet Rot are two diseases whicii, having obt-ained a 
hold on timber, are very injurious to the material and difficult to 
eradicate. There is a difference between the two, the latter 
being produced by putrification caused by constant cjcposure, 
but dry rot ia considered to be the more dangerous of the two, 
and if it attacks the portions of boats which are not exposed to 
view, serious trouble may be caused before discovery. 

Sound-looking timber, even when cut up into planks, may 
have bec-ome infected with dry rot by coming into contact with 
diseased wood, but there would be no evidence to the nalied eye 
until the spores of the fungus began to germmate, and it requires 
certain conditions for this to be brought about before the 
mycelium is developed. A still, warm, and damp atmosphere 
very quickly aggravates this trouble. 

There is no doubt that the initial cause of the rapid spread 
of dry rot is the imperfect seasoning of timber, accelerated by 
the laokof proper ventilation. The fungus filarpeat, or mycelium, 
when it attacks the heart wood, is very difficult to locate, unless 
the wood is seen to swell and the change of colour becomes evident 
on the outside surface. 

An inttiresting case came imder the notice of the writer a few 
years ago. A large sailing yacht was drawn up on one of the 
slips on the (.!lyde for surveying purposes and slight repairs ; 
when making adjustments to some securities of the keel it was 
found that dry rot was present, but the superficial indications 
were only slight. Eventually, after further investigation, it was 
discovered that tlie whole of thewood keel was rotten,tlie internal 
portion of which could actually be removed with the aid of a 
spade. There was no lack of money in providing every faoihty 
to prodnce a first-cla«a article, hut apparently the builders had 
been deceived in the quality of the material they were using, and 



92 SHIPS' BOATS ^^^1 

the circutustances only went to prove how difficult it is to dtscoverfl 
the trouble in ita initial stages of germination. 

When the surface of materia! ia attacked by wet rot and the I 
conditions are ripe for propagation, the evidence ia quickly seen 
in the form of mildew which can be wiped off with the finger. 
When pontoon lifeboats have been constructed during the early 
winter and laid on one aide in the boatyai'd until requisitioned 
by a vessel, it is not an uncommon occurrence to discover the , 
existence of the disease in opening out the hull for final inspection 
before delivery, I 

It is not intended in thia section t« investigate any chemical | 
theory aa to the cause of the disease, but it is very evident from i 
practical observation, that the presence of shavings, sawdust, 
etc.. left by the boatbuilders in the lockers at the ends of the 
boat and behijid the tank cleading. provide ready opportunity 
for distributing and carrying the fungus of dry rot should 
the material be in any way impregnated with the disease. In 
consideration of these difficulties it is very essential that masters 
of vessels should see that buoyancy tanks are periodically taken 
out and the inside of the planking and timbers thoroughly dried 
and repainted. Warmth and moisture acting in conjunction 
with one another are very active agents in producing decay; 
although timber of certain species, constantly immersed in water, , 
ia less snace.ptible to the extension of diseaae, as many readers 
may have toimd from practical experience in surveying the hull 
of wooden vessels, more especially in way of the bilges. 

The weight of timber infected with dry rot is greatly reduced, 
and the superficial evidence of the disease gives one the impression 
that the material has been burned, and pieces cut from the infected 
part are very brittle and if rubbed between the fingers can be 
blown away like dust. 

Much has been written on the subject by experts, and com- 
parative experiments carried out aa to the effect of dry rot on ■ 
various types of timber, but provided the timber has not been 
infected with the disease before feUing, it is very evident from the 
results of practical observation that if the material ia thoroughly 
seasoned and kept dry by periodical ventilation, it ia proof 
against dry rot. 

Trees are damaged sometimes by injury to the bark, and by 
the breaking off of branches due to their exposed position, or by 
the effects of frost bite. The injured parts are thus laid bare 
to the attack of parasites which give off a secretion and 
discolour the timber, eventually destroying the tree. 




TIMBER: CONVERSION, ETC. 93 

The liii'cli is vury liable to a particular kind of canker disease 
and if the bark at any time becomes injured, tliis Ehould be 
carefully covered up until tlie natural growth of the tvee preveute 
any further attack. 

Preservation. — In the days of wood shipbuilding the question 
of increasing the laating qualities of timber was one of great 
importance. Many experiments were carried out and much 
attention devoted to the various methods calculated to make the 
material impervious to the effects of the weather, but, whatever 
composition or treatment was used in the application of chemical 
impregnation, it was essential in the first place for the timber to 
be thoroughly seasoned. 

Salt was worked between tJie outer and iimer planks for the 
purpose of preservation and extending the life of the vessel. In 
recent years a system of impregnating the timber with an in- 
jection of distilled coal tar, under pressure, has been iu operation 
with excellent results and calculated t*) add to the lasting quahties 
of the wood exposed to the changes of atmospliere. No such 
methods are resorted to in the treatment of material for ordinary 
ships' boats, but in the construction of motor boats, the wood 
casing, watertight bulkheads, and surrounding structure, is very 
often chemically treated in order to make it fireproof. 

The precautions which are taken iu dealing with the preserva- 
tion of the wood during and after the construction of ships' boats 
are referred to in Section D of Part VII. 

It is not considered out of place in this section to make 
reference to the " Oxylene" process of producing non-inflavimabie 
Umber. The writer is indebted to the Timber Fireproofing Co., 
Ltd., of Townmead Road, Fulhara, S.W,, for a description of this 
particular treatment. 

The British Admiralty have for several years kept this subject 
under close observation with a view to obtaining the must snitahlc 
timber which ia " Hame-proof," Wood in a war vessel is kept 
down to the irreducible minimum, but it cannot be obliterated 
altogether in the construction, and the use of non-infiammablc 
wood could with advantage be used to a much larger extent in 
the construction of State rooms, etc., in passenger vessels of 
the Mercantile Marine Service. The matter is one worthy of 
further consideration in view of the recommendations and 
regulations of the International Convention for the Safety of 
Life at Sea. 

Material treated by the " Oxylene " process ia extensively 
used in the construction of motor boats and it is understood 



M SHIPS' BOATS 

tLat u boat hum been bitilt tkioughout, as an experiment, with 
wood subjected to this method of treatment. 

Timber jiubjected to this process is enclosed in a lar^c iron 
cylinder aud submitted to a steaming and vacuum treatment hj 
which the sap, air, and moisture in the poies of the wood are 
removed and vaporised. The wood is then impregnated under 
hyUrauhc pressure, with a solution of antipyrine chemicals, 
which Teplaces the elements driven out by the preliminary treat- 
ment. This chemical solution is considered to be preservative, 
antiseptic, and non-corrosive. It therefore does not injure metal 
brought into contact with the wood. 

The material is subsequently placed in spetdaily constructed 
dry kilns, where the water of the solution is finally dried off, 
the chemicals in minute crystal form remaining permanently 
embedded in the fibres. When heat ia applied to wood treated 
i)y the " Oxylene " process, the crystals iu the wood expand and 
form a glassy coating which excludes the oxygen in the air and 
prevents its combination with the wood, without which com- 
bustion is impossible. The greater the heat the mure the crystals 
expand, and although in time their chemical actitm is exhausted 
and the wood becomes charred, fresh crvatals take their place, 
80 that even when the wood becomes e-oiupletely charred through, 
no flame will be generated. This theory has been substantiated 
by tests on an extensive scale, and from samples submitted to 
the writer, it became quite evident when placed on a coal fire 
that they were absolutely " flame-proof." 

Seleotfon. — When selecting timber, inspection is made of the 
butt end of the log, which should be close, sohd, and sound ; the 
to]i is then examined to see if it corresponds with the butt end. 

DiSerences iu sound will indicate the presence and position 
of good and unsound timber, the perfect wood giving a sohd 
and sharp sound when struck with a hammer, white the decayed 
portions produce a dull sound, and the presence of inteiiial 
shakes will give the impression of the material being hollow. 

An old dodge is to place a watc^h against tlie butt end of the 
log, the ticking of which is plainly to be heard at the other end 
if the material is sound. 

A surface inspection is made for the existence of rind galls, 
spooginess at the pitii which denotes old age, decayed knots 
and discoioration at the ends which indicate decay. 

Straightness of grain is essential for material wliich is to 
be appropriated for the constnictiuu of ships' boats, except 
where crooks are reipured. 



I 



I 



TIMBKR: OOSVEHSION, ETC. 



96 



I 



Bright-looking timber in superior in quaiity to the dull, aud 
that which is smooth in working ia better than the rough or 
woolly. 

If the timber, when passed through the saw, has a tendency 
to clog the teeth, it is evidence of unauitabiUty. If when freshly 
cut it gives ofi an objiictionabie odour, it is invariably a sign 
of the presence of decay. 

Strength. — Particuhir attention is paid to the various species 
of timber to permit of the maximum amount of strength being 
incorporated into the structure of a ship's boat. The scantlings 
of material given in Table XIV, have been drawn up having in 
view the great streaaes to which a boat is subjected when being 
"lowered into the water with the full complement of persons on 
board. 

The lemile ati'ength of material ia the quality to resist a 
cohesive force or weight that tends to pull it asunder in the direction 
of its length. 

All material worked in a fore-and-aft direction to maintain the 
loQgitudtnal streugtb, should combine toughness and Jlex^lity, 
thettu being the quaUtios which combine the greatest degree of 
atiength and elasticity against fracture. 

Topre8erveatraightnoss,a largo meaaureof stiffneji»i& necesaury, 
and this can be measured by what is teitned the modulus of 
ela^iciljf, which ie a standard from which tiie elasticity of one 
material can be compared with another. It b the measure of 
the force or weight whicli is required to extend a bar, one inch 
square, to double its original length. 

In Tabic XIII. a comparison b made of the strength and 
elasticity of different woods used in boatbuilding and ship- 
building. 

Reference b made in Section B to the qualities of the various 
species of timber, and should be read in conjunction with the 
latter part of Section C of Part JI., deaUng with tiio strength of 
ships' boats. 

Measurement of Timber. — There are ceitain standards of 
meaaureiijeiit appliwl to timber when aold by the iiieit'.hant. 

A loud contains 50 cub. ft. of hewn or sawn timber, and 
40 cub. ft. of imhewn timber. 

A gquare b used generally when selling boarding, and b a 
superficial measurement and contains 100 sq. ft. 

St. Fetersburgh Standard.— i:\aa b a standard which b in 
general use in Great Britain and more particularly appUed 
to the soft woods such as fir and pine. One standard contains 



96 



SHIPS' BOATS 



165 cub. ft. or 720 lin. ft. of planks or deals of 11 in: 
by Sin. 

For weights of principal woods used in boatbuilding, reference 
must bo made to Part IX. 



TABLE XIU. 
STBSMam AND ELASTiciry ovTdibeb. 



Aah, Engliah . . . 
Afh, American 
Cedar, Cuba . . . 
Elm, English . . . 
Kim, Canada ■ 
Fir, Riga . . . . 
Fir, SpruDo, Caiiudu . 
Qieeiiivjart, Deiuoruin 
Hombeam, EoRlitili . 
Jurrah, Anatnuiaii 
Kauri, New Ze«i land . 
Laroh, Busai&n 



ToDH iier Hq. 111. 



3'9 «'8 8'0l 400 

2-9 3-7 I — — 

1'3 3'2,l-2 -AM 

20 2-fl I — — 

1-8 2-7,3'8 730 



' Mubogauy. Cuba . 
MBbogany. HunduraB 
Mahugany, Mi^xican . 
Uak, Englisli . . . 
UbIe, Ruiuian . 
Oak, Spanieh . . . 
Uak, American Whito 
Pin<>, Red, Canada . 
Pine, Yellow, Canada 
Pine, Pitob, Ami^ricaD 
Sabicu, Cuba . . 
Teak, Burmah . . 




HarUngs ol Foreign Timber. — Each country has its own 
particular method of branding or marking the timber for identi- 
fication purposes, but the following list will give the principal 
, sources of supply :— 

Canada. — The timber is stencilled with the traders' marks in 
black and white. 

United Slates. — The marks are made in red chalk ou the 
sides of the balks. 

Russia. — The ends of the timber are branded or stamped. 
Timber grown in the Imitate forests had the crown stamped on the 
ends. Hence the timber is known as " crown deals." 

Sweden. — The letters are stencilled in red on the ends. 

Norway. — The markings are made in a similar way to that 
of Sweden except that the colouring is blue. 

Qermany. — The letters are cut in on the sides of the timber, 
new tiie middle of the length. 



I 



PRINCIPAL WOODS USED IN CONSTBUCTION 

SECTION B.— PRINCIPAL WOODS USED IN THE CON- 
STRUCTION OF BOATS, AND THEIR RESPECTIVE 
QUALITIES 

' One of the difficultiea which is conimon to all who have any 
coimection with the timber trade, is the confusion of different 
names applied to the same species of wood, but grown in different 
localities, e.g. Baltic redwood and yellow deal, Oregon pine and 
Douglas fir, yellow pine and American white pine. These 
differences particularly apply to imported timber. 

There is a great similarity between certain woods, which 
makes it very difGcult for the inspector to identify the materials 
when they are seen apart. 

It requires aa expert to tell the difference between wych and 
English elm, beech and birch, also hickory and ash. 

In dealing with boat construction it is very essential to use 
woods whose quahtiea are best suited for the particular purpose 
required. 

The various species of wood worked into the hull of ships' 
boats are referred to La detail in the following order :— 

• English Oak. — Where stiffness and durability are required 
in lifeboats, together with the quality fur resisting climatic 
changes, as in lieadwooUs, stem, stempost and keel, English 
oak comparer very favourably with the very best of hard woods. 
It is hard, tough, strong, and elastic ; the grain is usually straight, 
uniform, and free from kiiots. 

The annual rings are ck)3e together and distinct. 
The medullary rays running at right angles ta the annual 
rings can be clearly seen, and when cut, produce a very fine, 
silky appearance in the surface of the wood. 

Other species of oak are grown in Austria and America, but 
are considered inferior to (he English quality, being much 
softer. 

■ Oak tends to warp and twist in the process of seasoning and 
deteriorates at the ends, imless the timber is placed \mder cover, 
Vrhich diminishes the difficulty. It ct^mtains a powerful gallic 
■cid, which corrodes iixin fastenings and tends to rot in way of 
theee securities. For this reason it is very essential that all 
iron bolts should be heavily galvanized. 

Oak is not adaptable fur cutting into small scantlings for boata' 
^1 apper or sheer strakas, or the inner gunwale of the box shape, 
^Bowing tu its tendency to split when under ten.'iioa and exposure 



96 SHIPS' BOATS ^^M 

to the weather. This is purely an expreflsion of opinion and t^e 
writer will probably be opposed by those who adhere to the 
practice of working in oak planking; ; however, it is considered 
there are limitations to the use of this wood, and it can be beat 
employed in the solid combinations forming the frame of the 
boat. 

Immediately the stem and stempost have been trimmed 
and scarphed to the keel, they shoidd be well coated with boiled 
linseed oil, varnish, or paint, as a means of protection from the 
weather. 

In selecting oak, care should be exercised to avoid all material 
which approaches a light brown or red colour, to guard against 
" foxiness," a disease which has already been referred to in the 
previous section. 

English oak is used for stems, stemposts, aprons, deadwoods, 
solid gunwales, keels, keelsons, and thwart knees. 

English Elm is a very difficult wood to work, being cross- 
grained, but verj' tenacious and not easily split. 

Owing to the absence of longitudinal fibre and its power to 
resist the influence of weather, it is largely employed in the 
manufacture of lifting blocks. The timber is very durable if 
constantly immersed in water and for this reason the planks of 
woiKlen vessels below the water-hne are usually of English elm. 

Wliere there is a tendency for water to accumulate and for 
the details of combinations to become exposed to alternate wet 
and dry atmospheres, English elm is considered to be of less 
value than English oak ; consequently it is advisable to have 
the deadwoods made from the latter material. 

English elm twista and warps a great deal during the procesB 
of seasoning. It has a very distinctive reddish brown colour 
and the piesence of sap is very marked by its yellow appearance. 
It is used for the backboards of sqnare-stemed boats and no 
material is better suited for rudders than English elm. 

During the war period, when the difficulty to obtain Eaglish 
oak or rock elm of suitable length was very acute, Kn g liah elm 
was used for gunwales by slightly increasing the scantlings. 

Wyoh Elm.— There is a great similarity in appearance between 
wych and English elm, the former being of finer grain with 
greater length of longitudinal fibre. The difference between tie- 
two is more noticeable in the growing trees, where the leaves of 
the wych elm are much smaller and possess a smoother surface 
than those of the English elm. Its use for boatbuilding is 
practically confined to Admiralty work, but sometimes in 



I 
I 



PRINCIPAL WOODS USED IN CONSTRUCTION 99 

latch boata the garbuards and adjacent strakes of planking are 
of wych elm ; it serves the purpose well in this position and 
provides a RfwKl solid caulking seam at the keel. 

Canadian ot Rock Elm. — This wood is well adapted for iiae, and 

extensively employed, in boatbuilding owing to its close straight 

. grain and freedom from knots ; it is very teoscious but wonder- 

I ftilly flexible and possesses few superior woods for timbers, 

keel, hog-piece, and gunwales. 

Great Britain depends entirely on the importation ot this 
timber from America for supplying the increasing necessities of 
the boatyards and shipyardB. 

Teak. — This is considered to be the very best quality of 
wood for the construction of the highest standard of ships' boats. 
It successfully resists the action of water, stands the climatic 
changes better than any other wood, is very durable and elastic, 
shrinks little, and is free from objectionable knots. Care should 
be exercised to watch for small worm holes. 

One drawback to hfeboats constructed of teak, is the increase 
of weight aa compared with yellow pine and larch, but the ad- 
vantages associated with the use of this wood greatly outweigh 
t^e disadvantage. 

Although the cost of production is greater, the additional 
outlay is more than compensated by the length of time the 
boats wiU last. 

The quality of the material is such that the weight is lessened 
I to some extent by the admissible thinning of scantUnga below 
I those of larch or other soft woods. 

Most of the leading shipping companies, whose vessels sail 
through tropical waters, insist that their lifeboats shall be 
constructed of teak or mahogany. 

It stands to reason, that timber grown in northern climates, 

^ such as larch and English ur wych elm, are unsuitable t'O witli- 

I Btand extremes of temperature, and it is the considered opinion of 

I many experts, backed itp liy the experience of masters of vessels, 

[ that all foreign-going vessels should be equipped with boat« 

[ constructed entirely of teak or mahogany, preferably the former. 

The timbers of boats constructed of eitlior teak or mahogany 

should be made from American rock elm, as the first-named 

woods are not adaptable fur the purpose. Tlie writer lias seen 

boatbuUders endeavouring to satisfy the requirements of some 

t owners desiring teak timbers, with the result that more timbers 
were spoiled than were actually worked into the boat. 
Teak varies greatly in weight, from 41 to 53 lbs, to the 



I 



t 

I 

t 
c 

I 



i 



100 



SHIPS' B0AT8 



cub. ft., depending upon the position ot the plank cut in relatioD 
to tlie heart wood. It seasons very quickly and is imported 
from Malabar, Java, Ceylon, and Moulniein. It possesses an 
uily infiredient which affords protection to the iron fastenings. 

Mahogany. — This timber is grown in the West Indies, West 
Coast of Africa, and in America around the Bay of Honduras, 
The annual rings are verj- distinct ; like teak, it is verj' durably ■ 
shrinks but little and does not twist or warp readily. 

Treea which are grown in swampy positions produce timbei 
of an inferior quahty, which becomes porous and light, 

The quality of mahogany varies considerably and it therefoi 
becomes essential to exercise the greatest care in selecting thtsl 
material for use in boatbuilding. 

Spanish nmhogany is distinguished from Honduras by its 4 

■ closer grain and darker colour. It is colder to the touch and 1 

possesses a silky texture with white specks in it, while the specks I 

in Honduras mahogany are black. 

Spanish mahogany comes from Cuba, Trinidad, and I 
Domingo, 

A large quantity of mahogany is shipped from the WestJ 
fViast of Africa. Lagos is much about the same in colour and 1 
as fine in texture as the Tabasco tnahogany, which is shipped from J 
South of Mexico, but is smaller in size. 

Gaboon wood should bo avoided ; it is iintcli lighter in colour I 
than the previoiisly mentioned types, resembling that of teak,] 
and very light in weight. 

It is veiy difficult at times %o tell the difference between tha 1 
various species of mahogany. 

In good class boat«, mahogany is used for planking and ia'l 
extensively eniploye<l for the double skins of lifeboats of Class II. 
and motor boats. 

When inspecting mahogany planking previous to painl^, ' 
one needs to carefully watch for small pin holes produced by 
minute worms. In the process of splitting up the planks, the 
saw fills up these worm holes, which, therefore, become difficult 
to discover before the boat is water-borne. The best remedy 
for this dp.fi'ct appears to be the insertion of small soft wood 
plugs, usually made of yellow pine. 

Beech,— There are limitations to the use of this material in 
boatbuilding, although it is tougher than English oak and yvry 
durable if constantly immersed in wat<er, yet when exposed to 
damp conditions it Koa a teudonoy to rot and it is therefore 
advisable to avoid it« use in rnrming the uunbinations. 



PRINCIPAL WOODS USED IN CONSTRUCTION 101 

Plane Tree reeemblea beech very much in appearance and 
nature; it also possesses the same features which make it 
undesirable for extensive use in the construction of ships' boats. 

Ash,— Whore toughness and elasticity are required there are 
few woods which surpass ash. It is grown in most parta of 
Europe and America. 

A difference of opinion exists among boatbuilders as to the 
efficiency of timbers made from ash, for the material possesses the 
disadvantage that when exposed to alternate dryness and moisture 
it soon rot^ and in this respect is not so durable as American 
elm for the purpose referred to. 

Ash will stand sudden and ^reat stress, and is therefore well 
adapted for tt>wing bollards and fco serve as a substitute for 
English or ^Vmerican rock elm in forming; gunwales. 

Young trees produce timber of greater strength than if allowed 
to grow to maturity. 

The groat bulk of oars are made of ash. 

Larch. ^Ninety per cent, of ships' boats constructed in 
Great Britain have larch planking. It grows in most of the 
northern districts of Europe and the quality of the trees culti- 
vated in the central and northern counties of Scotland is ex- 
ceptionally line. It is straight in grain, tough, and very durable, 
but shrinks quickly with a tendency to warp, so that care should 
be exercised to see that the material is thoniughly seasoned 
before being worked into the boat. 

Larch can be secured in fairly long lengths, but the timber 
grown in Great Britain usually contains more knots than that 
which is import«d from Russia and other Nortlieni porta, due 
to the fact that the trees in the British Isles grow with their- 
branches ncai-er to the ground. 

The fertile plains of England are not adapted to the full 
dovelopmeiit of the larch ; the latter needs an elevated, open 
sub-soU, with a clear atmosphere. 

Since the year 1725, when the larch was first introduced into 
the Highlands of Scotland, it has wonderfully flourished. The 
pukes of AtboU have alwa^-s taken a keen interest in the pro- 
duction of these trees and some of the finest specimens are to 
be found in the forests around Dunketd, Blair Atholl, and 
Mou2ie. 

The larch was first imported fi*om Italy, and it is of interest 
to note that during the lifetime of one of the Dukes of Atholl, 
some twenty-seven million trees were planted, which is a great 
contrast to the lack of initiative and effort of landowners of the 



102 SHIPS' BOATS 

present day, to provide new wood to replace the timber which 
is now being so speedily used up. 

Grood larch should be reddish brown in colour at the 
heart wood and yellowish white at the sap wood. The lighter 
coloured timber generally contains more knots than the darker. 
It cannot usually be obtained in sufficient width for use as 
thwarts, without running into sap wood. 

Larch roots make good thwart knees and breast-hooks for 
the smallest type of boats. 

Lifeboats constructed of larch planking are very strong and 
durable, provided they are carried on vessels which are not 
trading through the tropics. 

It is very evident that this class of timber cannot be obtained 
without knotij, owing to the number of branches on the tree. 
Some of the branches get broken at the tnmk and produce 
objecticmable black knotij, which are not '' well-collared " or 
firmly united to the surrounding timber. It is therefore essential 
that all knots in the planking should be carefully doubled before 
timbering, the doublings being well bedded in white lead paint, 
secured under the timbers by copper fastenings clenched over 
rooves. The practice of sim[)ly securing the knots by the head 
of a nail, having the point plied over on the inside of the planking, 
should be strongly condenmcd. 

The larch tree is very susceptible to a peculiar disease of its 
own, in the form of a canker, produced by summer frost, which 
interferes with the free circulation of the sap and forms a weak 
spot on the trunk: 

Cedar. — There is not much call for the use of this material in 
the construction of ships' boats in Great Britain. 

Many trees grown in various countries, particularly in America, 
are described under tlie name of cedar, hut are inferior in quality 
and do not bare comparison with the cedars on Mount Lebanon 
in Syria, referred to in Biblical history, whose magnificent 
grandeur and beauty called forth so nmcli comment from the 
Prophets of ancient times. Mount Lebanon is some 10,000 feet 
high and the cedars grew at an altitude of about 8000 feet above 
the level of the sea, but verv few of these trees are to be found 
at the present time. 

The cedars of Great Britain and Western countries are of 
a softer and more brittle nature than the material already 
referred to. 

The red cedar is grown extensively in the United States of 
America, is fine and straight in grain, fairly durable and light 



PRINCIPAL WOODS USED IN CONSTKUCTION 103 ■ 

in weight. It is from the red cedar that we secure the timber 
fnr the manufacturt; of lead pencils and is little used in ship and 
boatbuildinir. The codar that is worked into the construction 
of racing craft and boats, where lightness is of essential value, 
comes from the \\'est Indies aad Central America, the same 
districts which supply Great Britain with mahogany. 

Californian Redwood.— This matetial has been sometimes 
usedjor side se^tta and stowing chocks, but it does not appear to 
be able to resist the action of the weather and is considered 
inferior to pit^Ji pine. When pressure ia applied to the surface 
the material shows every mark. 

Cypress. — The common cypress grows in Asia Minor and 
Persia ; it is extremely light, very durable in certain situations 
and was used by the ancient Egyptians for making coSins, 
The timber that has a greater commercial value in Great firitaln 
comes from the swampy districts along the rivers and coast-line 
of the southern part of the United States of America. 

Louisiana cypress is used extensively in America for boat- 
building and can be obtained in good width and length, is free 
from objectionable knots, easily worked, straight in grain, soft 
and light. It needs to be carefully used and the material should 
be thoroughly seasoned. It possesses the reputation of shrinking 
end grain. Where firms in Great Britain have the material in 
stock they make use of it for the purpose of side seats in Class I. 
open boatfl. 

Pitch Pine. — Pines arc more resinous than firs and this enables 
the former to resist the action of water. The texture is close 
grained and the material more durable than the fir, the colour 
of the latter usually being fighter than the pine. It ia very 
extensively used in boatbuilding, for the purpose [}f planking 
motor boats, keelsons, thwarts, and side seats in ordinary open 
pulling boats. It is free from knots and sap wood and can be 
obtained in long lengths. 

The demand for this material in Great Britain has been 
greater than the supply, as it is largely used for ships' masts, 
derricks, and decks. 

Oregon Pine.— This wood is imported from British Columbia 
and the Western States of America. It can be obtained in great 
length and width and resembles pitch pine in colour and general 
structure. It« use is generally confined to the portion of the 
structure where pitch pine is permitted, except in the case of 
thwarts where strength is of importance. 

When cut into small scantling it is inclined to open out when 



I 



1(H SHIPS' BOATS 

exposed to the son. It can be secured in great width without 1 
running into aapwood. 

Baltic Redwood is the pine of the northern districts of the 
European Continent and, as the name sugjieats, is imported from 
the Baltic porta, and also from Norway and Sweden. 

It can be obtained in long lengths and is free from objectio 
able kDota,due to the lower branches of the tree being about thirty 
feet from the level of the ground. It is slightly red in colour, 
tinged with yellow, fairly tough and durable, is suitable foi 
thwarts and side seats, but inferior to pitch pine. ' 

The material is usually imported into Great Britain in deals 
and planks, and known in the South as the yellow deal. 

American Red Pine. — ^Vlthough this wood is inferior to the 
Northern grown timber, it is, nevertheless, of good quality and, 
where strength and durability are quahties of paramount im- 
portance, is greatly to be preferred to the home-grown firs of 
Great Britain. Its uae is confined to those portions of a lifeboat 
where Baltic redwood cannot bo obtained. 

Yellow Plne.^Wlierc lightness is of essential iiuportauce in 
the construction of a boat, or when the plankiny ia required to 
bo varnished instead of being coated with paint, yellow pine ie 
weU adapted for the purpose. It is free from objectionable 
knots, is straight in grain, elastic, and easily worked. The 
seams of the planking quickly " take up " and become tight , 
when immersed in water. 

The timber is mostly imported from Quebec and Ontario and 
the nortliern districts nf the United States of America, 

Wliile Pine. — There is no other tree which grows ao freely 
and produces timber so valuable on poor soils, as the pine which 
is to be found in most part« of Scotland. Its roots penetrate 
the fissures of rocks, and trees grow proliiically on the dry 
covered nioors, but they prefer an elevated situation. Thu 
material must not be crjnfused with that grown in the United 
States of America. 

Scotch Flr.^Uuring the shortage of home-grown lamber in 
Great Britain both white pine and Scotch fir were substituted for 
many of the imported wootls. Their various characteristics are 
veiy similar and their use is confined to side benches, thwarta, 
and buoyancy tank cleading. 

Spruoe.—This timber is obtained from trees grown in the 
same districts as the Baltic redwood, but is much inferior in 
quality. It is imported in deals and planks, usually tongued and 
grooved. It b uderior to red pine, pitch pine, or redwood, and 



THE EQUIPMENT OF A BOAT YARD 105 

when exposed tu the weather quickly splits and is thorufore 
unsuitable for side acuta and thwarts. It very- quickly rubs up 
into splinters after exposure and wear. 

Norway spruce is suitable for masts of ships' boats. 

The foregoing is a general description of the important woods 
used in the boat yards of Great Britain. There are other timbers 
which probably possess qualities quite equal to those already 
named and are suitable for the purpose of boatbuilding, but the 
difficulties of securing a steady supply by importation prevent 
them from being generally adopted. 

The United States of America has access to some of the 
finest timber in the world and yet tJie majority of ships' boats 
are constructed of steel, a feature which is probably due to the 
greater speed at which the steel boats can be completed as 
compared with those built of wood. 

SECTION C— THE EQUIPMENT OF A BOAT YARD 
The situation and efficiency of the plant of a boat yard have a 
du-ect bearing on the standard of workmanship and the financial 
success of the concern. 

The primary object in erecting a plant is to secure a satis- 
factory return for the monetary outlay. To obtain the best 
results it is essential to secure a situation for the boat yard that 
is adjacent to the water and within easy access to the railway. 
Yards situated on the batiks of the rivers Clyde and Tyne have 
many advantages in this respeo-t. 

The general arrangement of the plant must be designed bo 
as to keep the overhead charges down to the irreducible minimum. 
Each particular unit or machine shnuld be carefully considered, 
in r^ard to its relative situation to the work it has t<j perform. 

The whole idea in building the yard should be based on tlie 
desire to reduce manual labour to the lowest Umit and substitute 
the more speedy and therefore cheaper methods of modem 
machinery- Every labour-saving device shoidd be welcomed by 
the mechanic as a necessary means to secure the highest type of 
workmanship and so increase the efficiency of his particular trade. 

The machinery, building, and timber storage sheds must be 
individually considered in their relation U^ the actual operation 
of boatbuilding. 

It is the general opinion that the most satisfactorj' method 
of dtivinji; wood-working machines is by electric power, each 
machine being dtiven by its own motor. 



^K of dti 



106 



SHIPS' BOATS 



If engines and boilers are utilised they should be situated in a 1 
separate building outeide the main wall of the mill, to give greater I 
security from fire and obviate the nuisance of duet and grit j 
finding their way into the machinery. 

fndividual motors for every machine is the moat economical j 
arrangement eventually, even if the initial outlay is expensive. 

Wliere several machines are run from one motor, those 
which require the greatest power should be nearest the motor 
and the lighter ones pjacetl in their relative position as to the 
power required. j 

Good solid foundations are very necessary if lull advantage I 
is U) be obtained from the value of the machine. 1 

It pays the individual boatbiulder te erect his own plant 
for cutting timber from the log, and buy direct from the 
feller all the material he requires ; otherwise, he cannot be 
assured of well-seasoncil wood. He is also in a better 
position to cut to standard sizes, stock his sheds, and con- ' 
tinually and systematically feed thu lequiroments of the build- 
ing shed, 

The question arises as to whether the vertical frame saw j 
or the horizontal band saw is the better type of machine, For J 
ordinary shipyard work undoubtedly the former is considered 
of more general use, but for boatbuilding, where the latter haa J 
been installed, boatbuilders are enthueiastic as to its value for j 
their particular work. 1 

It enables the machinist to cut each individual plank to the J 
required thioloiess ; he can inspect the material as the log ia cut, 1 
and can adjust his thickness to suit the character of the log, 3 
especially when he is cutting near the heart. 

The writer has had some experience on the C'lyde and other 
yards of Great Britain with Messrs. Kansonie's patent horieontal 
log-band saw, and each of the boatbuilders using this particular 
type of machine has been perfectly satisfied. Other makes are 
probably on the market but the writer has not been brought 
into contact with them. 

Provided the operator does not try to force the machine 
beyond its power, the band mill should give perfeotlj' true cutting 
and is equally suitable either for breaking down logs, or for board 
cutting direct from the log. 

The waste in saw-dust is considered Itas than that made by 
the vertical saw or the lar^e circular saw. The latter machine is 
very difficult to operate in order to obtain true cutting for board 
work, and is very rarely seen in the boat yards. 



THE EQUIPMJiNT OF A BOAT YARD 107 

Anotlier advantage which the liorizontttl^band saw poasesses 
ovm' the vertical frame saw is that the deep pit associated with 
tlie lattei machine is not necessary with the former, because it i? 
fitted above the floor level ; all the operations connected with 
the working of the machinery can be supervised by one man. 

Boatbuilders who have the horizontal band saw installed in 
their yai^, state that for the amount of work it turns out, the 
power consumed is comparatively \eaa than with other types of 
machinea. 

An individual instance can be quoted where toak logs averafjtng 
22 in. in diameter wore cut into 3750 super, ft. of sawing in 
31 hours, which k at the rate of lOUO super, ft, per hour. 

Like every other similar class of machine it is essential that 
the operator should thoroughly understand tho capacity and 
use of the band oiill. 

Due attention must he given to the (juestion of keeping the 
saws in proper conditinu, and in order that every tooth shall be 
made to the same bevel and all the angles of the teeth precisely 
alike, it is much cheaper, in tlie hmg run, to have a separate 
compartment in the main machinery shed and erect a saw sharpen- 
ing machine, which requires very httle mdividual attention and 
less skill to operate than that which is needed to sharpen a saw 
by hand. 

Where wide baud saws are used it is necessary to have a 
brazing apparatus for repairs. 

It is an advantage to have an exhaust pipe arrangement for 
clearing tho saw-dust and shavings from the mill finors and led 
to a separate fireproof ahed. 

Planing Machines should ho of the three-knife cutter type; 
they are often nnuh abused and their cKciency considerably 
reduced in the eft'urt to plane every type oE wood in the same 
machine. It stands t« reason where cutters have been iisod for 
smoothing down teak, oak or elm, that poor resulta will be 
obtained on the surface of yellow pme or larch planks. Fur this 
reason a number of builders have two machines in their shed, 
and the results are worth the additional outlay. 

A good Band Saw is an indispensable accessory in the machine 
shed and for the purpose of cutting heavy crool^ for deadwoods, 
etc., it should be fitted with a canting table. 

A Swing Cut-oR^ Sawing Machine is a handy little machine for 
cutting oH butt ends of timber, oto., but it should be carefully 
used. 

A large and small Circular Saw are essential refjuirements, 



J 



108 



SHIPS' BOATS 



fitted with saws from 12 to 30 in., having adjustable iron tables ' 
and adapted for ripping, eroaa cutting, and bevel sawing. 
Provision should be made for fitting grooving saws. 

The Vertical Spindle is a machine which can be utiJised for a 
number of purposes. It requires the greatest care in operating, 
and there are very few men who are skilled in its uae. Means 
for protecting the machinist should always be provided. A 
greater return for the original outlay is obtained from this machine 
than any other in the boat yaul, if a skilled operator can be 
obtained. Two spindles are more satisfactory, revolving iu 
opposite directions, ao as to operate in the same direction as the 
grain of the wood. 

The timbers can be rounded with this machine very ex- 
peditiously, and the'bcarding taken oi! the stems and sternposte. 

The shed for seasoning timlKr should have a good protective 
roof with sides which will allow a free passage of air. It is a 
very short-sighted policy for any boatbuiider to attempt to 
construct lifeboats without providing facilities for properly 
seasoning the material. To allow oak, elm, or thin scantling 
material to indiscriminately lie about the yard exposed to the 
sun and rain, is to court disaster, and it would be a safe statement 
to make, that a very large percentage of builders do not exercise 
the care they should in this direction. 

Now that a boatbuiider can anticipate his requirements, 
through the principle of standaidisation of scantlings having 
been recognised, it is a great advantage to cut all the material 
to size and stow it away in a separate shed ready for use. Thia 
provision particularly applies to deadwoods, stems, etc. 

Veiy little foresight is exercised by the majority of boat- 
builders in designing the building shed to suit their requirements, 
especially where pontoon boats or open boats of (.'lass Ha are to 
be constructed. A considerable waste in labour and money is 
the result of maidng inadequate prtjvision for suitable mechanical 
power to lift and transport the boats during and after construction. 

The operation of removing a boat from one berth to another, 
or transporting it to a lorry or railway truck entirely by manual 
labour, should be discouraged, as the method is antiquated and 
co.tly. 

The shed should therefore be designed with overhead rails 

and mechanical appliances that can be easily operated by two 

, and the pontoon boats easily turned over or removed to 

another berth without interfering witli the men already engaged 

on the construction of boats situated in other parts uf the shed. 




THE EQITPMENT OF A BOAT YARD 



109 



The follnwinji general Bcheme in operation in one of the boat 
yards recently erected on the river Clyde is to be commended : — 

A central overhead rail runs throughout the length of the 
building shed, connecting each individual berth. Provision is 
made for transporting the boats through the sliding doors 
immediately opposite the berth by nmning bogies imder the 
keel and transferring them through an open passage outside the 
shed, to a gantry fitted with mechanical means for lifting the boat 
on to the railway truck or lorry. 

Benches should be fitted in each building berth and the 
latter numbered. Full information giving sizes and particulate 
of boat must be placed in a prambient position, so that individual 
mechanics are in possession of aU the requirements. Many 
unnecessary mistakes have been made through carelessness on 
the part of the foreman in giving verbal instructions to the men 
which have been raiaunderstood. All the particulars relating to 
scantlings of material and details of specification should not only 
be kept in the office, but circidated among the individuals who 
have to construct the boat. 

It is also a good scheme to arrange the berths so that as soon 
as one boat has been so far completed on the keel board as to be 
easily removed, it can be finally finished off in the adjacent 
berth. This methinl of procedure enables the work to be carried 
out systematically and ensures a quicker iintput. The machinery 
shed is kept constantly busy and the steam chest is practically 
in full operation during the whole process (tf construction. 

Very few boatbuildets have the facilities for making their 
own lifting -hooks, inm knees, and other forged iron work. It is 
the general practice on the Clyde bo obtain all the iron fittings 
from a smith, and the system of standardisation of details ensures 
the Wfirk coniing to*the*boatbuilder with the least amount of 
trouble. 

TTie manufacture of buoyancy air-caaes is a trade which can 
be undertaken to the best advantage by a tinsmith or sheet-iron 
worker, and 'the large^'percentage of boatbuitdera will find it 
cheaper and more satisfactory to deal with the expert who Is 
able to gauge the correct amount of metal to be used fur the 
I particular size of boat under construction. 



SECTION A.— CONSTRUCTION OF CLASS Ia OPEN 
LIFEBOATS 

ScantUngs.^Referc^Qce has already been made tu the necosaity 
iif a reoofiiiised scheme of scantlings, whitih should become 
opprative in all yards, to enable the boatbiiilders to select the 
most suitable material and of such dimensions as will be sufficient 
to meet the heavy stfessea which come upon a loaded boat when 
beinf5 launched from the davits. 

The detaiU shown in Table XIV. are being worked to by a 
large number of the boatbuilders ; the various sizes are based 
on the length of the boat. If reference is made to Table VII. it 
will be seen that there is very little variation in the dimensions 
of lifeboats, and particularly those which have beeen suggested 
as standard sizes. A large number of fii'ms have already adopted 
the principle of standardisation, the outcome being that the 
work in the yard becomes simplified. 

All the work of the allied trades associated with boatbuilding 
is made much easier if the detail fittings, such as iron thwart 
knees, breaathooks, etc., are ordered on a basis of length of boat. 

The various lengths of open boats of Class Ia and Ib have 
been gro\iped together, on the assumptirm that eac'h particular 
length of boat possesses definite proportions in its dimensions ; 
that when loaded and suspended from the davits certain maximum 
stresses are encountered. Each particular detail of construction 
has therefore been designed to reduce the effect of these stresses. 
and to maintain at the same time a reasonable factor of safety. 

Lurid at^coimts of disasters at sen, when launching the ship's 
lifeboats, have often given a wrong impression of the actual 
facts, but, nevertheless, it is very essential to take every known 
means of combating the "unusual circumstance," and tu provide 
life-saving appliances that are strong enough and effective for 
the purpose intended, having a factor of safety which will enable 
the ship's officers to maintain complete confidence in the boato 
they have under their supervision. 



I 



21 


i 
Transoms . . . 


1 

1 

1 

English B 

1 

English Elm 

- - f- 


1" 

12" 


21 




RUDDKR . . . 




22 


22 




Teak, Elm *" 
Plank EancL 


10 ft. 






G AU« i E OF Fasten- 
in* IS .... 


-> 


23 


Risings, Solid Gun^ 
Ends and Till 

Note. — All Rooves ti 

.- - - * 

Wrought Iron (2 i= 
Norway Sj 


23 








24 


Ringbolts . . . 


24 


25 


Li:N(jTir OF Mast ' 


' 25 



Xoti\—\n additi onal length of boat not catlings of a higher 
c are rot i uired . L ^'^ /«<^"^' P- 1 1 1 • 



grade are required 



1 



I 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 111 

It may be argued that a better p]an would be to baae the 
acantlinga on the number of persons carried. Owing to the 
small variation of dtniensiona associated with length, it practically 
amoimts to the uame thin^ ii the scanthngs are ba^ed on definite 
lengths of boat, Thescbeme shown in Tables XIV. and XVIII. 
has been in operation since October, 1916, in the largest boat- 
building centre in the British Isles, and probably the largest in 
the world. The writer baa had sufficient experience to acluiow- 
ledge the simplicity of the working; of the scheme. Take one 
instance alone : when it becomes necessary to order the iron 
knees for a particular boat, all the boatbuilder needs to quote, 
is the length of the boat, and the knees are delivered to him from 
the smith, having the correct depth to suit the position of the 
thwart in relation to the gunwale, and the holes are drilled 
to allow the fastenings to centre the rubbers and gunwale, as 
arranged by the boatbuilder. 

The Board of Trade have now issued detailed instructions, 
making the latter applicable to all districta in the United 
Kingdom, and the information in this text-hook practically 
covere all their requirements. 

Bevellinfi the fastenings to catch the combinations or knees 
liaving their throat securities attached to the binding atrake 
below the rubber, at the ends of a boat, are practices which can 
be avoided, if a standard scheme is in operation between the 
allied trades. 

Liftiug-hooks and sail areas are also based on the length of 
boat. 

It need hardly be mentioned that a common minimum scheme 
of scantlings, made apphcable to aU districts, provides a fair 
basis for competition among boatbuilders, and ensures a satis- 
factory type of boat, if construction is carried out in accordance 
with the specifications. 

A fair latitude is given in the list of materials to enable the 
various firms, in widely scattered districts, to have accees to 
timbers which are easily procurable. 

It ia obvious to any one associated with the indnstrj', that 
no matter how detailed ai'.d explicitly arranged a scheme of 
scantlings may be, there are two essentials which are of the 
greatest importance, and must be carried out if the lifeboats are 
to serve the purpose for which they are intended, viz, — honest 
workmanship and the use of smsotunl material. 

Preliminary Information. ^Before construction is commenced 
on any ijoat it is essential for the boatbuilder to secure all the 



112 SHIPS' BOATS 

nGc«sary infomiatiou from the shipbuilder that will (enable him 1 
to proceed with the work without interruption. The following J 
details should be given by the shipbuilder when ordering the boats | 
for a particular ship, viz. :— 

(1) The class of boat to be constructed. 

(2) \\'hether boat forms part of the Statutory Equipment | 
of fie vessel. 

(3) Whether double bowed or square stem. 

(4) Whether vessel is engaged in the Foreign or Home Trade:. 
(6) Dimensions of boat (L X B X D), 

(6) Material of planking. 

(7) Whether full equipment ia required to be suppUed. 
- (S) The position of the liftini; -hooks in relation to the fore , 

edge of rabbet at stem and after edge of rabbet at stempost, oi 
their relation to the extreme ends of the boat ; in any case, it 
should be definitely stated wliere the positions of the hooks are 
to be taken from. To avoid any discrepancy the distance 
between the hooks should also be given. 

(9) The type of davit under which the boats will be suspended 
or stowed. 

(10) Any additional fitting required by the shipbuilders which 
is not mentioned in the Rules for Life-saving Appliances. 

Having this detailed information, the boatbuilder can proceed 
on the construction without interruption, provided he has arranged 
for a continuous supply of material, and given out in good time 
the sub-contracts for delivery of iron work, equipment, etc, 

Large firms usually stock a quantity of thwart knees, breast- 
hooks, etc., and prepare themselves to meet every emergency by 
anticipating the requiremeuti} of the shipbuilder. 

A great deal of work has often been unnecessarily scrapped 
when the boats have heen nearing completion, througli lack of 
thought on the part of the boatbuilder t«i secure this preliminary 
information from the shipbuilder, before laying down the keel 
of the boat. 

Keel. — The foundation, or what is generally referred to aa the 
" keel board," should be made from sound and substantial 
material, from 111 to 12 in. in depth and from 4 to 5 in. in 
thickness. 

Thekeel board is tied to good heavy foundation blocks, anchored 
in the groimd and prevented from movement by piles or stakes. 
The ground should be of solid formation and the blocks arranged 
at short intervals under the keel board, to prevent hogging or 
In this respect some firms give the keel board a 



CONSTRUCTION ^F CLASS Ia OPEN LIFEBOATS 113 

slight camber to make up for the weight of the boat acting on 
the keel between the points of support, when stowed in position 
on the Vessel, as the tendency at one time was for a sagging stress 
to be exerted on the keel. Now that the stowage chocks must 
be fitted at the quarter-length of boat from stem and stempost, 




MOG ptecc 




\ MOO ^p/£ce\ 



(8€EL£D) 




B 





aoARo 



f 



FOUNDATtOrf SIOC^ 



I 
I 

r ' 

I 



f^ 



ff/rOO^O LB¥£L 



Fio. 30. 

A. arrnngeiiioiit of keel boanis and fouudatluiw. 
K, method uf hei'uriiiR hoR-]dece to keel and garboardH. 
(/. iiietho<l of w>curinK timbers to hotf- piece and sarboardn. 
D. uection of keel board arrangement. 



there appears to be no necessity to arrange for any camber on 
the keel board. 

The general arrangement of keel board and foundation is 
shown in Fig. 30 a and d. 

There is a limiting depth between the top of the keel board and 

1 



114 SHIPS' BOATS 

the ground, which should not be less than 15 in. This distance 
allows suflicient space for the free use of the hammer when 
clencliing up the plank fastenings, but more particularly when 
driving in the timber nails from the garboard strake to tie turn 
of the bilge. 

Incidentally, it provides a good opportunity for an inspector 
of ordinary proportions to watch the quality of the planking as 
progress is made with the construction. 

The keel must be in one length and selected from material 
which is straight in the grain, all objectionable knots and swirls 
being carefully avoided. The scantlings vary from 6^ moulded X 3^ 
sided, for a 30-ft. boat, to 4''x2J" for a 16-ft. boat. 

The most suitable material for keels is American rock elm, 
which is of fine, close, and even texture, free from knots and gives 
c<msiderable kmgitudinal strength. Next in order of suitability 
is oak, which must be straight-grained and free from knots ; 
otherwise, unless the material is thoroughly seasoned, it opens 
out in way of the knots, paiticularly if the lower portion of the 
keel has cut through a knot running in a'vertical direction. 

English and wych elm have been used for keels as substitutes, 
during the period of the war, by increasing the scantlings, but, 
generally speaking, they should be dropped in preference to 
ro(;k elm and oak. Grey elm should be avoided on every occa- 
sion ; it is nothing more than swamp wood and lacks strength, 
llexibility, and resihence. 

'J'h« keel is placed on the keel board and kept perfectly 
straight in a fore and aft dire<!ti()n by driving in wedges between 
the k<;el and cleats attached to the keel board, as shown in section 
at Fig. 30 J). 

The top edges of the keel arc champhered to enable the 
garboard strake to have a square landing edge, which should be 
carefully performed to provide a satisfactory scum for caulking. 

Stem and Sternpost. — The combination between the stem, 
st'Crnpost. and keel, nmst be of an efficient character, and the 
material employed of the best (luality. The stem and sternpost 
is usually of oak and select^'d from well-seasoned timber grown 
to shape. The necessity for good crooks to be litted at the 
combinations is obvious to the practical man, but during pre-war 
days there was always a very great difficulty to satisfy the 
requirements of the boatbuilder in this respect. The opening 
up of the market for home-grown timber in recent yeiirs, has 
created a better supply of crooks, and this supply has always 
met the demand if sufficient trouble was taken to inform the 



r 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 115 

timber merchant of actual requirements. The usual procedure 
has been to blow up the roots of trees by dynamite instead of 
lifting them by the more tedious process of digging ; so that 
the majority of crooks were obtained from branch wood. The 
necessities of the boatbuilders having become known, timber 
fellers are now able to give a better selection of material. 

In the first place, standard moulds should be kept by the 
boatbuilder to enable him to apply the same to the timber before 
conversion and secure the beat advantage in regard to grain. 

A pleasing shape to the stem makes all the difference to the 
appearance of a boat. A sharp, stumpy stem worked in to 
avoid a long crook does uot allow the planks below the bilge to 



I 




Fio. 31. — VertiuBl sCBq>b of sl«m to kwl. 



be Unished off at the hood-ends in graceful curves and in con- 
lonnity with the lines of the boat. It is somewhat difficult to 
explain how this occurs, but the difference between the two 
types of stems and their effect on the planking, is very apparent 
in the boat yard. The grain of the wood at the heel of the 
stem, where it scarplm with the keel, should run in the same 
direction as the grain of the keel. 

I The eomiection between the keel and the stem and stern- 
|>ost, so fur as ships' boats are concerned, is efficiently made by a 
vertical or a horizontal sL^arph. The vertiail scarpk is the more 
popular one. and is shown in Fig. 31. The method provides a 
better opportunity to secure a suitable crook and lends itself to 
simpler attachment than the horizontal scarpb. The vertical 



11(> 



SHIPS' BOATS 



scarph practically means a "' half-check '' and the keel and 
Htoni are well secured by at least five through fastenings ; these 
should be of substantial gauge, not the usual timber nail and 
clenched over roovos, but copper rod of 4 or 5 S.W.G. and 
clenched over washers ; rooves are far too thin for this purpose. 

As shown in Fig. 31 many firms snape away the fore upper 
edge of keel and make the stem to suit ; such an arrangement is 
considered to be a stronger connection. 

The horizontal scarph is illustrated in Fig. 32, the length 
of which must be arranged to take three fastenings. The heel of 
the stem nuist of necessity be a perfect crook, otherwise the 
connection is of little use. The centre of the three fastenings in 








•i 




Fui. 32.— HfH-izdiitil rtCiirpli of sti'm to kcil. 

the scarph is usually left until the doadwood is worked, when a 
l(mg bolt is arranged lo catdi the keel, stem, and deadwood. 

Whether the stem is secured to the keel with a vertical or a 
liorizcmtal scarph, the full thickness of the keel must be preserved 
right out to the face of the stem, and the bearding arranged to 
commence from about four inches above the top of the keel with 
an easy curve. The bearding is about one and a half inches in 
breadth on the face of the stem in 30-ft. open boats and about 
one inch in small boats. A strong stem can be made by 
preserving the thickness of the back out to the face, for a dei)th 
of about 14 in. from the stem head, and running into the 
bearding in a similar fashion to that arranged at the heel. 

The sizes of the head and heel of stem and sternpost are 
shown in the scantling Table XIV. 

Care should be exercised in fitting the scarph so that the 
stem and sternpost plumb the centre line. 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 117 

There is very little difficulty to eecure suitable mat-erial for 
the stempost, unless the boat is of the double-bowed type. The 
necessity for a crook does not arise aud the usual vertical scarpli 
is worked as a connection to tlie keel and secured in a similar 
manner to the stem. (See Fijr. 37.) 

When the connections have been completed and fastenings 
properly clenched, the stem and stempost ace mitde to plumb, 
and their heads are .secured by shores to some pei'munent part of 
the boat shed. 

Reference is made to the Htem and stempost rabbets when 
discussing the question of planking. 

There have been alternative methods of connecting the stem 
to the keel, worked at one time or another in the various boat 
yards. Tlie method shown at Fig. 3,1 is a Hlight modification to 
the vertical searph as illustrated in Fig, 31. It will be noticed 
that a check is taken out of the deadwoiMj, which provides 
additional strength to the securities of the stem scarph. The con- 
nection shown at Fig. 34 ie not recommended, although it is very 
simple and entails the minimum amount of labour. A few 
years ago the majority of the yards went so far as to simply step 
tlie stem on tlie keel, without even making a chock in the latter, 
relyuig on the throat bolt for the main security of the comiection. 

Fig. 35 is an illustration of a practice sometiuies seen in the 
construction of motor boats, where tlie deadwood is made to 
dovetail between the stem and keel. The stem and apron are 
in one piece, the rabbet for the hood-ends of planking being cut 
as indicated in the figure. It is very essential that the deadwood 
should be of selected material and very carefully cut and fitted. 
The efficiency of the conneirtion greatly depends on the securities 
and the quality of the workmanship. The writer has a personal 
antipathy to any form of combination which does not jirovide 
a gcHid faying surface for the reception of the planking, and the 
practice referred to is an instance of the difficulty. 

Fig. 36 is a further illustration of the keel and stem comiection, 
and is made with a dovetail check taken out of the keel, having 
a throat bolt security to the deadwood, just clear of the check. 
This arrangement ia quite a common practice. A superior 
method is that of increasing the thickness of the stem at the heel, 
BO as to combine the dovetail check and the horizontal scarph 
and make provision for three through fastenings. It is very 
essential to secure material which has been cut from timber 
grown to proper shape, otherwise the connection is useless after 
tie boats have been in service tor twelve months. The lifeboats 



i 



118 



SHIPS' BOATS 



constructed for vessels owned by Mesais Alfred Holt & Co., of 
Liverpool, have their stem and stempost connections made in 




Fia. 33. 



Fro. 34. 



accordance with the metliod described, and tliis is sufficient 
evidence of its v^alue. 

The stem and sternpost heads are kept down as low as possible 
so that they do not project above the gunwale as to be a 
source of danger. They are so shaped as to easily clear ropes and 
wreckage. Some firms cut the stem and stempost heads and 
tlie aprons flush with the gunwale, others allow a slight projection 



ro^£ £0€i 



Ci 'ff^t 



J" 




4PftOf^ 



H-^ f- .--' ^ 




6 



7> 



fy/'f I 



' ffECL 



oovcrA/t 

CHrCM 



^ 



Fio. 35. Fifi. 3ri. 

Altorn.'itivr methods of lltting .sU*m to keel. 

above the stem and Htcrnpost knees, but well rounded, so as to 
preserve a finishoil apj)earance. 

The bearding of the stem can be done with the aid of the 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 119 

spindle, but the operation is a tricky one and needs the skill of an 
experienced machinist. The use of the machine referred to saves 
much labour, gets through the work speedily, and gives a finished 
appearance. The stem is shaped at the band saw and can be 
practically prepared ready for dressing, and it is in such detail 
work that the value of a good man supervising the machinery 
comes into operation. Many firms still rely on the unnecessary 
use of the adze ; this tool could at least be much restricted if 




• 



t -V. : 





^ceL 



SM£C SA/VO 




Fi(!. 37. -Vertical soarpli of sternpost to ko«*I. 



the men had the opportunity of being trained in the manipulation 
of the many labour-saving devices. 

The rake of the sternpost is from 4 to G in., so as to pennit of 
the full floor being worked well aft. 

Hog-Piece. — To provide a good landing edge for the garboard 
strake and a solid connection for the timbers, a hog-piece is worked 
in one length on top of the keel and checked under the deadwoods. 
The material is usually American rock elm and should be of 
straight grain, free from shakes, and not less than 1 in. in 
thickne^ss, to ensure a solid foundation for the caulking seam. 
The h(;g-piece is secured to the keel by stout screws, about 
2| in. in length and G in. apart, worked in reel fashion as 
shown in Fig. 30 ii. These screws, therefore, come midway between 
the timbers and are arranged after tlie positions of the latter are 
indicated on the upper surface of the hog-piece. 

The width of the hog-piece is given for every length of boat 
in Table XIV. and is arranged in each case to provide a good 
bearing for the garl>oard plank landings and the timber fastenings. 



120 SfflPS' BOATS 

Defectively caulked seamB at the sand strakes, or, what is 
usually termed south of the border, the garboard strakes, are 
often caused through the timber nails being " dump " instead 
of ''through" fastenings, and clenched over rooves as shown in 
Fig. 3() c. The operation of clenching the timber fastenings 
through the hog-piece should be undertaken at the first oppor- 
tunity and before the keelson is fitted in position. 

The spacing of the timbers governs the pitch between the 
keelson fastenings and is therefore a multiple of G in., and 
usually not more than 24 in. The whole of the fastenings, in con- 
junction with the position of the timbers, are marked in position 
on the liog-pieoe, immediatdy the latter is temporarily secured 
in positi<m on the keel. 

Deadwoods. — Keference has already been made to the 
necessity of strong and efficient combinations, and more attention 
has recently been given to the quality, form, and scantlings of 
the deadwoods. The im{)ortanGe of having good material free 
from cross grain, and selected from timber grown to shape, is 
obvious. The deadwoods form a solid stmt to the stem, 
sternpost, and keel, distributing the stresses to the frame of 
boat, which arc received through the lifting-liooks. The form of 
the dcadwood should be such as to receive the maximum amount 
of support from the timbers, planking, and combinations, and 
for this reason it sliould be sided so as to preserve a fttU faying 
surface for the reception of the planking. This provision also 
possesses tlie added advantage of preventing the accuumlation 
of water and dirt between the planks and deadwood, which is 
an important matter in view of the position of the deadwood 
being at the ends of the boat, covered in, and very rarely inspected. 
This precaution is somewhat difficult to carry int^) effect with 
the largest ty[)e of lifeboats, as it requires a very big crook to 
obtain the fall faying surface from plank to plank at the midship 
end of the deadwood. 

Provideti a faying surface of 3 to 3J in. is preserved for 
the double fastenings at the hood-ends or plank landings, it is 
admissible to fill in the intervening space between the deadwood 
and planks with filling pieces, efficiently secured to the deadwood 
before the planking is worked. These filling piece^s should be 
well bedded in thick white-lead oil-paint and arranged as shown 
in Fig. 39. 

It has rtxently been approved for the throat of the deadwood 
to 1)0 not kvss than the depth of the keel plus 1 in., the siding to 
be sufficient to give a faying surface of 3 in., exclusive of the rabbet. 




CONSTBUCTrON OF CLASS Ia OPEN LIFEBOATS 

Deadwuods cut from material {ijrown to shape are more easily 

procured for the stem than for the aterapost, owinj; to the sharp 

angle between the steriapost 

and the keel being about 

100". 

It is usually impossible to 

secure more Ihan two timbers 

across the <lea(l woods, the 

heels of the reuiaiuinn timbers 

at the ends, forward or ftft, as 

the case may be. being checked 

into the deadwooda, which re- 
lieves the plank fastenin<;s of 

some of the stresses at this 

position. 

Wliere difficulty occurs in 

securing suitable dcadwoods 

which would provide a full 

fayint; surface from plank to 

plank as rihown in Fig. 40, a 

practice has been in operation 

in some yards to fit a sole 

pi&K on tlip keel and under 

the deadwood. The straifilit 

grain of the sole piece allows 

the full bearing of its thick- 
ness for atta<;liment to the 

planks and can be brought 

sufficiently towards amidships 

to become incorporated with 

the keel plates of the lifting- 
hooks, and thus take ite full 

share of the stresses which 

come upon the boat at this 

particular position. Such an 

arrangement i.t shown in ele- 
vation at Fig. 41 and the i'lti, 40, 

" bnilt up " deadwood is quite 
' a common practice for fishing vessels constructed on the west 
I coast of Scotland. 

The faying surfaces of all the combination.^ should have a 
I good soaking coat of white lead paint, before being secured in 

position. 



122 



SHIPS' BOATS 



It is usual to arrange for five through fastenings in each 
deadwood, the upper one forming the scarph connection to the 
apron, ^\llen boats are lifted at the extreme ends, as in the 



»ff£lZOS 








^i^ao 



Fii:. 41.-- Huih-up deadwood. 



" Welin " type of davit, it is necessary to pitch the fastenings to 
enable them to be iiicorporateil with the keel plate of the lifting- 
hooks. Moulds are made from the curvature of the deadwood 
and given to tlie smith f<»r application on the back of the keel 




•' / 




/ 

7' 



Qrr~-: ' 



/ 



He-^L. 



y 



y 



Fh;. 42.- -Pfwitioii of i?topwat<*rs. 

I»lal<s U) ensure a close lit between steel and wood, thus giving 
ellic.icnt/ b(*aring for securitie^i. 

The connection between deadwoods, keel, stem, or sternpost, 



I 



CONSTRUCTION OF CF^ASS Ia OPEN LIFEBOATS 123 

can be made bj | in. to i'',- in. galvaniaed iron rod, and clenched 
over washers, or preferably, by the use of galvanised screw 
bolts, having their points clenched over the heads of nuts. 

The latter method allows a final adjustment to be made to 
the fasteninga before clenching, and greater power is provided 
for drawing the faying surfaces together. 

To prevent leakage at the connections of combinations, 
itopwaUrs, made of anft wood, usually yellow pine, are inserted 
in the poaitionB shown in Fig. 42 and marked A and B. 
These Btopwatera prevent the passage of water into the boat as 
a result of leakage through the scarphs or keel seam at the dead- 
wood ; a provision which is often overlooked in the rush to 
complete the planking. 

Apron.— The apron is that portion of tlie frame combination 
which is attached to the stem or stempost and pi'ovides the 
surface for securing the hood-ends of the planking. Very little 
difficulty is experienced in securing suitable material as tliere is 
practically no curvature in its form. 

Oak or elm is usually employed and caie must be exercised 
in cutting the apron to shape, to preserve sufficient material for 
fitting the hood-ends of the planks. 

We find here another argument fur the use of standard 
moulds. Careleasness in trimming or cutting the faying surfaces 
for the reception of the planking ia often responsible for tlie 
objectionable practice of fitting sliver jneces between the planks 

■ and the apron t^ make up for the deficiency of material in tlte 
latter. The siding of the apron should be so arranged as to pro- 
vide a fayui^' surface of 3 to 4 in. for the hood-ends of planks, so 
that with this faying surface and the rabbet cut out of the stem, 
there ia ample material for the reception of a double row of fasten- 
inga. Attention should therefore be given to see that the apron 
I is trimmed so as to be in alignment with the form of the boat. 
The securities of the apron to the stem and stempost are 
similar tti those which pass through the deadwood. The upper 
bolt is l]ttie<i through the stem, apron, and gunwale breaat-hook ; 
the second is the ring bolt to which the painter is attached ; 
obeerving that a ring bolt should be fitted at both ends of the 
boat and be of substantial scantling (see Table XIV.) ; the 
third bolt passes through apron and stem ; but the fourth one 
usually picks up the luwer breaat-hook in boats of 24 ft. in length 
and upwards ; the fifth bolt forms the security between Uie 
apron and dcadwoul scarph with the stem or stempost. 
A full detail of the formation, connections and securities of 



I 




J 



126 



SHIPS' BOATS 



Fig. 45 was taken iiom a phatograph of a boat in course c 
construction at the boat yard of Messrs Eobert Eodfi;er & Co., 
Greenoi'k. It sLowa clearly how the apron and deadwooda ' 
closely fay against the planks, givinj^ very little opportunity for 
water or filth to lie between tJie surfaces, and in this case, where 
the timbers cannot cross the centre of the boat at the ends, they 
are checked into the deadwood. 

Incidentally, this plate also shows a doubling fitted behind a i 
knot in a larch plank, gripping two timbers and properly secured j 
with copper nails clenched over rooves. 

In districts where suitable crooks are easily procured, it is J 
not an uncommon practice in building fishing boats and motor 
craft, to have the apron, stem, and deadwood, in one piece, 
instead of being separately connected together. The writer has 
seen some very fine jobs completed in yards situated on the I 
lower reaches of the Clyde, with solid end combinations, but J 
the scheme also has its disadvantages, particularly when any J 
portitm of the combination needs repairing or renewing. 

Keelson, — When the combinations have been fitted, securiKl, 
and the framo of the boat made to outwind and pluuib the centre 1 
ti.f-e-ico.f/tu \ia.ii, they are secured I 

in position at the keel J 
board and to some i 
permanent part of the I 
boat yard. The posi- 
tions of the timbera j 
are marked on the hog- 
piece and the hood- 1 
ends of planks marked I 
on the stem and stem 
post. 

Before the planking J 

is commenced it is, 

Fw 47.— Section of kwluiiUk.-pl«onrombiii<ilion. "sual for the keelBOft. 
to be cut to leug^. 
The keelson is an eesontial part of the structure and acts aa a 
very substantial support for the heavy load of a fully equipped 
boat. It is arranged with the section as shown in Fig. 47, i.e. 
moulded to a size greater than its sided dimension ; or, in other 
words, its depth is greater than the width, which allows for 
greater strength in a longitudinal direction. 




The keelson should extend in 



B far forward and aft 



as the combinations will allow and become incorporated with the 




CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 127 

faatemngs of the deadwoyds and keel. The keekon should be 
BO worked aa to take the whole of the fastenings of the lifting- 
hook heel plates slb illustrated in Figs. 43 and 44 which gives 
additional support Ui tlie boat. 

At this period of the construction it ia only necessary to cut 
the keelson to length and fit the ends to the form of the dead woods. 
It ia finally placed in position when the boat has been planked 
and timbered, just immediately before the thwai-ts arc ioHerted. 
The material is usually of pitoh pine, oak, elm, or Oregon pine. 
The common practice among boatbuilders is to take the line 
of least reai.stance and fit the keelson on top of the timbeis. 
This method allows a free drainage from one side of the boat 
to the other. 

A very efficient means of binding the backbone of the boat 
and giving better support to the mast-step is to check the keelson 
r the timbers so that its lower surface fays with the upper 
surface of the hog-piece, the depth of the keelson being increased 
to allow for the checking. 

The disadvantage claimed for the latter method is, increase 
of cost due to extra labour required in fitting. The slotting of 
the keelson for the timbers must be very carefully done, other- 
wise opportunity is given for water and dirt to find their way 
between the faying surfaces and timbers, which encourages wet rot. 
It ia only in high-class work that the slotting of the keelson is 
undertaken, and therefore more care has to be exercised in the 
details of construction. 

The two methods referred to are illustrated in Figa. 48 and 53, 

The keelson is well secured to the keel and deadwoods by 

[ iiall-iuch galvanised iron bolts spaced about 2 ft. apart, 

" either clenched over washers, or secured by nuts above washers 

I and having their points clenched over the nuts. To give a solid 

I bearing in way of these securing bolts, solid chocks are fitted 

I between the two timbers, extending the full width of the keelson. 

In the case of some types of motor boats, tu provide a low 

I seated motor it is not always practicable to fit a keelson, and in 

I tiiese cases the bilge stringers are increased in scantlings to make 

up for the loss of strength. 

Boats carried by trawlers are not usually fitted with keelsons, 
I as they would interfere with the particular work these vessels 
I »re engaged in. 

Transom,— In completmg the description of the construction of 
[ the framework of an open boat, reference b made to the methods 
\ of fitting the transom in a square-stem boat. Preferably, the 



-HIPS" BOATS 



rrATL^t in ?£i'-'i^«: "•:•? w- :ri.*c in. oe* piece and sdectcd from 
5»^;i>« z-h: EnJ^ii -^iin- riaiv^canj. '"r teak. The heel of the 






^SS"^ 5*^ * 



\r 



r> 



-Cl 



HI. 



CJ. 




If thero :- Ivika 



- s^ - -.•_-^— •' •- » 



.r i. •» 



>: ^t aT^ Ar.jle. as shown in Ilg. 49 
i.i< ni, die di£cultv is asualljr to be 








ripr 



UH 



V. 



-1 -i -£ 



I 



.""5- V 



^fc - • 



Fi-;. 4:'. 



K: . .--■. 



,1 »'J 



Fi«;;. 01. Fig. 52. 



found at the .seam «.r j.^int, il lit tod iii balvf^. or at the heel. To 
obviate tliis drawback, the wiiter La^ ^ouiotimcj? seen a dove- 




.Ci. 



*f££^5C'f 



.CALV i^C^fAt. 



*«J^|J^'*^ 



THCiCM , 







I • 
I I 

I 



Fn;. 53. 



s jrt^^r '"*"'"" ^''^ '^''^^ ^"'^ ^^« «^-"p-t. 



r 
I 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 129 

It b very difficult, at times, to secure sufficient breadth in 
tiie material to allow the traiiaom to be in one piece, and it then 
becomes necessary t« work a joint, Fi^. 51 shows a method of 
joining the two pieces of transom together with the aid of a 
haH-check and secured with copper fastenings clenched over 
rooves. , This makes a good solid job, provided the securities 
are closely spaced, and should any shrinkage take place in the 
transom the joint can be lightly caulked without unduly opening 
out the seam. 

Another practice, as illustrated in Fig. 52, is to fit a Je/Uher 
flip between tlie two pieces of transom, but this method does 





Pm. 54.- 



if-n of »lom|K)!l iiend, t 



« nnd trnnHom. 



not give the solid bearir^ for a light caulk as the one previously 
referred to. 

Where fastenings are clenched over rooves which are in 
contact with hard wood, such as oak, it is usual to slightly sink 
the rooves into the material. 

The transom is also secured to the stempost with clenched 
fastenings or long stout screws. 

The common practice is to cut the stempost short of the 
cross-piece. A method, which it is considered adds strength to 
the combination and helps to prevent the transom coming away 
from the sternpost, is to mortice the head of the stempost into 
the cross-piece as shown in Fig. 54. 

The Methods of fitting fashion pieces to take the hood-ends 
of planks and sliver pieces at the heel of transom, are dealt with 
Then discussing the question of " planking." 



RHTPS" BOATS 

The full thickness of the keel is carried out to the after edge 
of the uterapoat and the bearding; is coinmenced a few inches 
above the keel, so as to take the rudder-braces, as shown in 
Fig. 27. 

No particular rule can be laid down as to the width of the 
transoni, which if generally about two-thirds of the breadth of 
the boat. 

PlinUng. — Provided the scanthnga of the combinations are 
satiMfactory, it is safe to state that the most important operation 
in connection with the constraction of a lifeboat is tho planking. 
In the first place, to secure a fair fonned boat, with eaey curvature 
of the planks and satisfactory soleing for the landings, it is 
absolutely essential that moulds should be erected. The question 
of a suitable form and the various salient features which must be 
observed before the moulds are erected, have been dealt with in 
some detail in Part II., Section C. 

The continual alteration of dimensions of boats, with no fixed 
minimum dimensions or recognised standards, have been largely 
responsible for the unsatisfactory method of planking a boat 
" to the eye." It stands to reason that the boatbuilder cannot 
possibly stock hia yard with moulds suitable to every type of boat, 
hut a» standard dimensions are gradually becoming the rule in 
most districts, there is every incentive givea to the builder to 
work on systematic lines. 

From tlie writer's experience in visiting some of the lai^est 
boatbuilding yards in the country, unless section moulds are used 
in every case, one caimot be sure of two boat« being alike. The 
men actually constructing the boat are usually dependent on the 
foreman for the shape of the plank given by the plank mould, 
and tlie strakcs are worked ami fastened according as it suita the 
tasto of the individual. When the planking above the bilge has 
BO far advanced as to give some indication of the breadth, it often 
happens, in the absence of section moulds, that the form has to 
be " jiffled " to suit, a practice which is responsible for bad 
Boleing, bringing unnecessary stress on the plank fastenings, and 
eventually results in split planlcs. 

Three section moulds are considered the minimum number — ■ 
one at amidships — and one at the quarter-Iejjgth from stem and 
Bternpost. 

Some firms adopt swing moulds, i.e. half sections which are 
pivoted at the middle line and can be swung from side to side. 
The general practice is to work to fixed moulds which are not 
removed until the'operation of planking is complete. 



CONSTRUCTION OF CLASS Ia OPEN IJFEB0AT8 131 

There are three methods of planltinfj lifeboats ad'ipted in 
Great Britain: the " muUiplc-skin'' (see Figs. 71 and 72). the 
" carvel " (see Fig, 55), and the " clinker " (see Figs. 67 and 87). 

No doubt exists as to which is the best principle of construc- 
tion. The multiple-skin worked diagonally is adopted in the 
highest class of pulling and motor boats. This method provides 
an exceptionally strong and efficient boat, which in many instances 
lasts the life of the vessel. It naturally follows that the cost of 
production is greater, the weight is increased, and there is greater 
difficulty in repairing a boat when damaged, owing to the insertion 
of the inner skin and the textile material between the two 
thicknesses ; but where a vessel is constantly running through the 
tropics, the additional initial cost to the shipowner is more than 
repaid after a few years' service. 

The " carvel " method of planking is considered to be next 
in order of value for strength. A boat built on this principle 
has flush planking, the edges of which are fitted close together 
with the whole inner surface having continuous support from the 
timbers. A carvel-built boat will stand more knocking about, 
with less chance of having damaged planks, than one constructed 
on the " clinker " system. 

A " single " skin boat should be built with just as much care 
and attention as is given to the " niultiple-skin " boat. The 
usual experience of the superintendent or the inspector is, that 
the simpler the method of construction, the less precaution is 
exercised by the boatbuilder. 

The " clinker " method lends iteelf to quick procedure in 
construction, and therefore gives early delivery. Eadi plank 
runs in a fore-and-aft direction, the edges are lapped or landed 
one im the other, the breadth of the landings is usually about 
J in,, the limit beiug J in. Boats thus constructed are easily 
repaired after being damaged, and with simplicity of working, 
coupled with speedy delivery and a minimum of coat, these factors 
provide the main reasons why the majority of lifeboats supplied 
to merchant vessels are built on the " chnker " method. 

The ttuckuesB of the planking varies in accordance with the 
material used. Yellow pine and larch planks are J in. to |i in., 
while wych elm, teak, and mahogany are worked about |',> in. 
lees in thickness. A good practice existing among some Arms, 
when buildii^ yellow pine or larch boats, is to work in the two 
Btrakes of planking adjacent to the keel, of teak wood. 

The section moulds are prepared and secured in position. The 
position of the planks are marked on the midship mould, and on 



^^ Tht 
^^1 positio: 



132 SHIPS' BOATS 

the stem and stempost aft^r the standard allowance for sheer 
has been t.aken into consideration. The usual sheer recognised 
in the boat yards is | in. to the foot, which is slightly more than 
4 per cent, of the length of the boat, the regulation standard. 

The breadth of the plnnk^ should not exceed 5J in., with the 
exception of the ^arboard and its adjacent strake, which are 
permitted to exceed this limitm*^ breadth up to 7 in. The 
landings must not be le^s than | in., but are usually ^ in., so that 
the width of plank showinji would be not more than 4| in. 

Boats of 21 ft. in length and downwards usually have planks 
not exceeding 5 in. 

In order to j)reserve a uniform appearance to tjie planking, the 
binding strake is increased in breadth by the thickness of the 
rubber, so that the actual breadth of planking showing, is 
the same as the adjacent strakes. 

The particulars given in Table XV. will be usefid to ascertain 
the number of planks required in various boats of Classes I A, Ib, 
and III., which are built on the ** clinker " principle. If these 
numbers are worked to, the breadths of the planks will be within 
the standard Umits. 

TABLE XV. 

Minimum Number of Strakes of Plankino in (.^ltnkkr-built Boats of 

CiJ^ssES I A, Ib, and 111. 



Diiuensions of boats. 


Total No. of strakes. 


300' X 1)0' x:V7r>' 


17 


29-o'x«-7r/x:M)' 


17 


28-0' X 8-5' xH-r/ 


10 


27 0' X 8-25' x:{-4' 


10 


2H0'>.80' x:j-2iV 


15 


25o'x7-7r>'x:Mr)' 


If) 


24 0' X 7-5' x:50' 


14 


230' X 7-5' > 20' 


14 


22 0' x 7-25' X 2 -75' 


13 


210' X 70' X2-7' 


13 


20-0' X 0-75' X 2-0' 


12 


19-0'x<i'5' x2r)' 


12 


I80'x()-2r)'x2'4' 


11 


17O'x(>0' X2-.S5' 


11 


IHO'X 5-75' x 2-3 


11 



Nothin<^ beats hand-dressed planks. If planks are passed 
through the planing machine, they should be tou(h(»d up with 
the hand-plane before being worked into the boat. 



CONSTRUCTION OF CLA(^S Ia OPEN LIFEBOATS 133 

It stands to reason, if the blades of the planing machine are 
used for oak, teak, elm, and other hard woods, one cannot expect 
to secure a proper smooth surface on the larch or yellow pine 
planks, unless a planing machine ia kept expressly for the purpose 
of treating the soft wooda. 

The two great esaentials for securing a satisfactory job with 
the planking, ate seasoned niatertal and careful attetUion to delaUs. 
In the first place, unless the timber has been properly treated and 
pinned at least twelve months before being required, after three 
months' service the boats will become lealtj' and of little use as 
life-saving appliances. 

Unseasoned larch is easier to work during the various stages 
of construction than the bone-dry material, particularly during 
the operation of planking. Seasoned material needs greater 
care when drilling for the faaterdnga at the landings, and par- 
ticularly when the copper nails are driven through the timber. 
Roughly treated, the material splite. Ail the defects of seasoned 
timber are seen before the wood is painted. The difficulties 
with unseasoned planking occur aft«r the boat is used in service 
and when the material shrinks after exposure t« the atmosphere. 
The boat cannot hold it^ form, and something is bound to go, 
consequently the planks usually split along the landings between 
the fastenings. 

Dry material produces a hard sound when touched with tlie 
hand plane, and gives a glossy surface to the planks when finally 
dressed. Unsi!asuned material always remains dull, irrespective 
of the time spent on the dressing. 

Planks should not be kept in the steum diest longer than 
I'i minutes, otherwise all the resinous nature of the material 
which is required to counteract the effect of the weather will be 
driven out. If the material is unseasoned, veiy little advantage is 
to be obtained by keeping the planks in the steam chest for 12 
hours. 

The scheme that pays the boatbuilder is to anticipate his 
requirements and to keep sufficient material in stock, which has 
been well pinned down under cover for a reasonable length of 
time. 

It is unsatisfactory to place bad material in the hands of a good 
workman, for he will never take an interest in his particular job, 
and logically it is waste of time tor both employer and employee. 

If good material is given to a boatbuililer. it becomes an 
I incentive for him to turn out better work. 

Planking cannot be scamped. Piecework is a " buybear " 



134 



SHIPS' BOATS 



to honest workmanship. A good job is the fiiat conoMleiratioiiy 
and speed should take a secondary place. If one can onl^ 
secure the former it naturally follows that speed wiU very qiucldy 
follow. 

The garboard stroke is the first plank adjacent to the keel. It 
is sometimes called the sandrstrake^ and is worked from tiie 
stempost, forward to the stem, so that the outer edges of the 
scarph butts lie aft, and are thus protected when the boat is 
movin<{ forward through the water. The method is shown in 
Fig. oIBa. The garboard planks require careful fitting at the 
ends of the boat, and together with the adjacent planks have a 



-CLAMP- 





-BQSS PUNCH — 



^ 



c tcyATioH - roove: set - 
" " " """""""^^=» CZ2) 

END SECTION 
OFHE AVYSET HEAVY PUI^H OR 'bOLLV*' 




Fio. 55. 



Fio. 56. 



great influence on the rest of the planking as to maintaining a 
good form. 

Tlie planks are held in position ready for securing, by the 
aid of clamps or tangs, as illustrated in Fig. 50. Particular care 
should be exercised in drilling the holes for the fastenings. The 
bitt must be kept square to the planking, otherwise the nail is 
brought too near the landing edges. This precaution is veij' 
necessary in way of the bilge. 

After the nails arc driven, the rooves are placed over the 
point of the nail and hardened home against the planking with 
the aid of a boss ]>unch (see Fig. 56). 

The whole of the plank fastenngs between the timbers, and 
also the timber fastenings within arm's reach can be rooved and 
clenched by one man with the aid of the heavier type of boss 



I 



CONSTRUCTION OF CLASS 1a OPEN LIFEBOATS 135 

punch. The roove is inaerted over the uail point with the punch 
on the roove. By strilcing the head of the nail squarely v.-ith a 
light hammer the weigJit of the punch drives home the roove 
against the plank. The projecting point of the nai] is nipped with 
the pincers to within |*'j in. of the roove, and the heavy clump end 
of the boss punch is then held on the nail he^d and the clenctiing 
completed with the li^ht hammer. 

The rooving and clenching of the timber fastenings from the 
bilge to keel is a double-handed process, one person holding on 
the head of the nail with a fairly heavy and Hat-headed hammer, 
while the roove is driven home and the nail clenched from the 
inside of the boat by another person. The hghter type of boss 
punch, shown in Fig. 5(i, is used during this operation. 

In mahogany, teak, and wych elm planking, a ahghtly deeper 
countersink is given to the drilled hole in the face of the plank 
than when using yellow pine and larch, to accommodate the head 
of the nail. The main thing to avoid is the breaking of the surface 
of the plank, so that the head of the nail lies flat on the surface of 
the pliuik, 

Too much eraphaaia cannot be given to the matter of plank 
fastenings ; it is one of the most important items connected with 
boatbuilding, and yet so many firms content themselves with 
allowing boys and young girls to undertake the work. The 
practice of sinking the heads of the plank fastenings below the 
face of the plank is shoddy and pre-historic ; regulations should 
be made to prevent the practice from continuing. In fairness to 
the boatbuilders of known repute, these important details ought 
to be embodied in the governing specification, for in many 
districts the standard is set by the firm who is not so particular 
in the main essentials, which make all the difference between a 
boat and a basket. 

Itisavery objectionable practice t<> sink theheadsof the plank 
and timber nails beyond the surface of the planking. The plank 
fastenings are usually rooved and clenched in the one operation, 
and the timber fastenings are driven into the plank and timber, 
but are not rooved and clenched until the thwarts are fitted and 
the boat stifiened up. 

The purpose in sinking the nail heads is to allow for the final 
dressing of the planks, but this is often caiTied to excess in the 
effort to save copper. With this method it is impossible to ascertain 
whether a timber nail is properly hardened up and clenched. 
In hardening up the naU, unless particular care is exercised, 
I it ia bent, and the fact of driving the head of the niul 



136 SHIPS' BOATS 

beyrmd a prriper countersink, and forcint; its way through the 
material, i^ re.spon.sibIe for many split planks. The whole 
operation lends itself to farelesi>nesc> and roui:h work. 

A far .superior practice, and one that should be enforced bv 
re<^latioas. is to dreas the planks by hand, and when drilling 
the planks, to so arrange the bift or gullet that a very slight 
cr)untersink is taken out of the plank surface, and only just suffi- 
cient as to brini! the nail flush with the surface of the plank. 
When the point of the nail is clenched over the roove, it draws 
the plank landin;^.s together, because the head of the nail has a 
proper bt»arin_' and is not drawn through the surface of the 
material. A slack fastening is thus very quickly discovered and 
remedied. This practice necessitates care, and hammer marks 
on the plank surface should be avoided. All that is necessary to 
comjiletc the surface is the use of sandpaper. The nail heads are 
left bare and no putty Ls therefore recjuired. 

Some shipowners insist on this method in the construction of 
boats, and it is a practice which has been in operation with the 
Admiralty for manv vears. 

The plauk scarphs are about -IJ in. in length, and secured with 
two rows of copper nails clenched on hkivcs. The Admiralty 
practice for pullin;i boats built on the " clinker " system, is to 
secure the butts with one row of copper nails plyed over on the 
inside surface of the plank at the after ed<re of the scarph, and a 
second row plyed over on the outside surface of the plank at the 
forward vd'^n of the scarph. 

When tlie fast«'ninizs are sunk below the plank surface for 
final <lressin^', the onlinary scarph butt is often mined by the 
iiniount of material j^laned away in the vicinity of the row of 
nails at the after ed^^e of the scarph. 

To strenizthen the butt connections, some firms fit a stout 
doublin;^ b(»hind, connextiiiLT two timbers, the butt fastenings 
beinir roovc^d and ch^nched on the doubling,', as sh(>wn in Fig. 57. 

The f)lain scarph butt is tin; method which creates the least 
amount of labour, but it is inferior to the cJuHrd butt. The latter 
method must be carefully undertaken when cutting the check out 
of the |)lank. t.o pnjvent the saw sinking too deeply into the 
pljink. The two mt^thoiis {ire illustrated in Figs. 58 a and B. 

.\n old practire, but. nevertheless, a good one, is to insert thin 
brown paper or canvas steeped in boiled linseed oil, between the 
faying surfac<»s of the scar[)h. which ensures a watertight con- 
niu'tion. provided good securities are also made. In any case the 
faying surfaces should be well treated with oil paint. 



CONSTRUCTION OF CIA8S Ia OPEN LIFEBOATS 137 

A proper shift of huUs should be given to the planks, and it is 
usual to try and arrange for not more than one butt in a strake. 




m 



3 



O : : o o 



r f 



I 



o o 

O o 



— ..... .^^ACtb^t* ^ A€.€.tA^^.Ju^tUIA,<J!JU.A.K£€>t^Ie^A 



LyJ 
win 




^1 



Fio. 67. 



In boats of 19 ft. and downwards it is quite common to complete 
the planking without a butt in any one strake. 

There should be at least three planks between the butts in the 
same timber space, and butts in adjacent strakes must not be 
nearer to each other than 3 ft. It is also advisable that the 
butts of the garboard strakes should be properly shifted, for the 
common practice is to fit the butts in the same timber space, so 
that the planks on the port and starboard sides can be prepared 
on the bench at the same time, i.e. the lengths of the planks on 



Arr 







LAI^^€0 SCA^P^ 



cneofeDsaufpH 




B 



Fio. 6S. 



both sides of the boat in a particular strake will be the 
same. No plank should be less than 6 ft. in lengthy and 



_ 'jr 



i»!^iT? 



-..-• : :i • " - : : :. :i> i. v:i - i^ ri. 4ai£ I$S-W.G. for 








.(t 




TsZ'. «v 



:. :■- - •;.-•: v_-i ":.- :• ..:v:..rL> : :• oti'i: cers ^ecome more 
,;.■■-- .-::. :. ... ■ _-: --.-" :: r.: :he "old-time" 
;:-•:. ■ ' :.-* . v ^ : -r^.:., :.. :- -u:<:aiiial wiU be 

'-,i/.-i: ' *'.- - - .'.-* 1 -■-■ • :•»> ^',.-' '^ ■ {w% 

'/:.■: •• :-: : : .:.—--. :: :. :. :Lr Adn-iraltr for all 

;/ ....u:^ % .-4-- :.; v. :■ - i r^: .--:^: : Ta:.:.« -.:::.i.:e to the plank 

'i:': .';.*•;' a:*'...- ; i. •.»•:.■ -; -:.• -.v:. ::. F:.. "V* {■:..• vides a roove 
'.i'fi ■'# Ml': 4rj -'i.'r r.vi* '.v-.^Li ::.v :.a:! :- i!vi:iLed over, the 
/'/'/v«; -jf,K-, jjiVi tij*r piriiir: ci:.«.i \vry . ::-:. s:.lir,<. Fii:. tjli shows 
jifi if/iji. "/•/«•'] roov#- wiiir-h i< -lijiitiy ci.'iiwx and of heaWer 
.■.'.;i/itlif,:/ .,/, tijat w-}i<;rj tli..' u-t»:-iiin_ \< rl.-neheil up, the whole 
.!'i/f;i/.«r #if t.h«: ////,•.'<; jr taKifj:.' a lull bt-ariu:. "U the jilaiik. 

' ;if"fijl atNrf,t.ii,ri A\u\\\i\ be driven to tht* method of forming 
tiii/| .•.«/iniri;/ th«: h^d-nuU of plankiiiL'. With at least 3 in. of 
Uvfux'j ^MxUu'M t,ii til*! aj>ron and deadw.KHl. ample bearing is 
Kiv«:ij ioi t)|f: fJouMi: row of fa.-tenini'.s. 



'CONSTRUCTION OF CLASS U OPEN LIFEBOATS 139 



1 

^P In boats of 24 ft. in len<^th and uvcr. braas screws am placed 

^ in the row nearest the rabbet, so aa to provide for a good security 

when caulking the " hood-ends," tot with ordinarj' copper naits 

the tendency of the cauik would be to lift them. The inner row is 

oE copper nails. 

Boats below 24 ft, in length have the planks at the " hood- 
I ends " secured by a double row of nails, slij^btly reeled to prevent 
, the splitting of planks. These nails are usually roser-beaded. 

It is not sufficient to simply cbampber off the edge of the stem 

or stempost to house the " hood-ends " of. the planks. A proper 

rabbet must be taken out, leaving at least ]■'[ in, of solid wood, 

I 80 that the pknk takes a bearing on the stem and stempost, 

I which provides an efficient caulking seam, otherwise, if only a 

1 chamfer is taken off, one is continually caulking into the seam 




Fio. 61. 
Method of aeoi 



■ing liood-cnds of planks. 



I between the apron and the stem or stempoat. An illustration 
\. of the method referred to is shown in Fig. 62. 

One of the disadvantages of fitting a stem and apron in one 

E|iiece of timber, is discovered when it is necessary to renew the 

■item or stempost, and for this reason it is essential that both 

C0W8 of fastem'ngs should be in the apron. There is, therefore, 

little advantage to be gained by having the end row in tbe stem 

and the second row of securities in tbe apron. 

A good practice is to cut the rabbet for the sheer-strake 

beyond tbe ordinary plank rabbet so that the former becomes a 

means of protection to the remaining plank seama or " hood-ends." 

Tbe landing edges of the planks on the apron, are usually 

soaped away as shown tn Fig. 63. which allows the full thickness 

I of the upper edge to be carried out to the stem or stempost. 
The soaping away is done when the plank is fitted in place, and 



IVl 



SHIPS' BOATS 



ll« whr.le 0/ tke w<«xl is (Jtm hOT tl» «|>i»r ei- i —J, j„v 
« .h„ .he pUd. ,„rW i»™di.«,v'S:^'XlS^»^ 
l»«m.,n. This .luipuw ur.v hu to b. tot oirfoDy 3Se ud 
the practice 15 a doubtful one tor eSciencT aa it i, _, 'JlI 
.Wl. Unless the chisel is properl.T ^d," i„ .md, ^J^ 
u taken off the upper edue of the pUidi .t til. «in»i.^rS, 
»n eitent that when the caulldna tool is used it ^ibthe tern 
"■"'.t the »tem apron. In any case, the watettiiifiia, Di»ctii»IlT 
•lefK-mLs on the efficiency of the caulk. «""y 

A .siip.Tior method of completing the " hood-ends " of planb 
w to ta[«.t or chamfer holh planks, so that at the stem or atasiinat 
rahto, the plank landinas ate half checked, wUch inoTiders 
ptojier bearing; for the screw fastening and tjie wjiole cf tiia 




i 




|,l.,.k.> 



yi». ii3. 

M'tli'xlH uf nnujiini; luK'd-cn'lii of planke. 



: wull syrtii-od together, apart from their connection 
iiliirifiti'iiis. A ;:noiJ solid ending is thus provided fop 
ttii! iiin\Um'j. *'"il, and this method is yreatly to be preferred to 
ttn: |iniit,ii« of Dtilysnapiri;.' away the upper plank landing. The 
opi-r!il,iiin can \i<; dornr tin the bench before the plank is secured. 

H':UiTi:ni:i; should he made t*) Fij^. ti4. The advantages refened 
to an- obtuiiK!)! tit a -.'leater extent in the case of a " square 
Ht<-ni " hofit, when ending the jihinks on the transom. 

Till! writer liaH repeatedly seen evidence of the value of CfU«fuUy 
" iitteil hood-ends.' Fig. i(J7 shows a lifeboat of Class Ia which 
wuH damafjed durin;{ the opemtion of bein^ lowered from the 
|''*vit« in a hurry, after the vessel had been torpedoed. Coming 
•"Violent contact with the ship's side, the gunwale was smashed, 
*hich brought Uh> mucli stress on the securities of the plaoka to 
^ AproQ. Thti fastcuiQ{;s were ordinary copper nails, but the 



the a 




I 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 141 



endin<,'8 (rf tlie ptaoks were made on tlie half-clieck principle, 
so that when tlie planks came away from the apnm they were 
well held together and prevented from ripping. This boat waa 
safely brouf^ht to port, mainly depending on the air-cases for 
buoyancy. Hence the necessity for periodically testing the 
watertij^htnesa of the buoyancy tanks. 

Caution should be particularly observed when working the 
planks at the transom of a " square stern " boat, and with a view 
to providing a good fayinf; surface for the plank endings, a fashion- 
piece should be worked aroimd and well secured to the transom by 
throujih copper fastenings clenched over roovea, which allows an 
ample bearing surface for the double row of fastenings. This 
fashion-piece should be quite free from short grain. (See 
Fig, 116.) 

One of the weakest positions in a aquare-atemed boat, and 
where there ie the greatest difficulty to obtain a satisfactory 
security for the plank endings, and also where there is a 
tendency for the plank to split, ia Immediately under the counter 
or just below the heel of the transom. These difficulties are 
obviated if sliver pieces are worked between the deadwood and 
transom, and well secured to the stempost, which provide a proper 
bearing for the plank just where it is most needed. The sUver 
pieces have the additional advantage of preventing the accumula- 
tion of dirt behind the deadwood. 

Tlie heela of the fash ion -pieces are made to butt on the sliver 
pieces. 

It is possible for these projecting pieces to be left <)n thu stem- 
post when cutting it to shape at the band saw, but the process 
ia difficult, the common practice now being to fit them separately, 
and bed the faying surfaces in whit« lead paint. 

The matter is of more importance than this explanation 
probably conveys to the mind of the reader. 

The method referred to is illustrated in Figs. 60 and 66. 
Considerable care needs to be exercised in working the garboard 
and the two adjacent strakes at the transom and stempost of a 
" square-atem " boat, so that they may be gradually eased to lie 
fair to their work. This applies particularly to the garboard 
strake in the smaller type of boats, as the plank is worked from 
the horizontal almost to a vertical position. 

Fig. 65 A shows one method of ending the garboard plank on 
the stempost, which requires very careful treatment to prevent 
the plank from splitting, when driving home the fastenings. 
It poeaeesee the advantage of completely covering the deadwood. 



i 



142 



SHIPS' BOATS 



Fig. 65 B illustrates an alt'emativo method which allows the 
garboard to lie more evenly on its bearing without giving an 
undue amoimt of twist. This arrangement is practically the 
same method which is adopted in ending the plank on a double- 







FAS HfON r/£C£ 




ELEVATION 
Fig. 05. — Methods of ending enrboard plank on the deadwood. 



bowed boat. The garboard in this case does not fully cover the 
deadwood, and it is nexjessary to fit two additional stopwaters, 
but it «:(ives great advantage to the boatbuilder in preventing 
split planks at this position. 

TJic planks at the turn of the bilge are kept as narrow as 
possible to enable the minimum amount of soloing being taken 



I 



CONSTRUCTION OF CI^SS U OPEN LIFEBOATS 143 

off the landinji ettgcs, but sufficient to allow tie upper plank to 
lie well into the timber without uudiily reduciaf; ita thickueas. 
{See Fig 67.) It is the practice in some yards to slightly increase 
the thjckness of the material, because there is no doubt an area 
of we-akness exists in way of the bilge, which is restored U) 
some extent by the fitting of bilge keelsons. 

The use of section moulds facilitates the operation of securing 
a satisfactory job with the eoleing of the plank landittga. Care 
should be exercised, particularly just beyond tJie quarter sections 
towards the ends of the boat, where the bend in the plank is the 
greatest. Insufficient attention is often given to the process of 
soleing or chamfering the plank landings, to such an extent that 
some firms reiy on a thread of cotton 
being caulked into the seam to secure 
watertightness. With fastenings sunk 
below the surface of the plank, this 
practice is undesirable, for when the 
cotton swells the strain draws the 
fastenings a still greater distance 
through the phmk, the boat is left in 
a weaker condition, and no advantage 
is gained from the point of view of 
watertightness. 

As each plank is worked, the landings 
are well coated with good thick oil-paint. 
Provided the planks are secured in the section 

proper manner, a very good practice is pm. (Hi. 

to coat the landings with a composition 
called blaiT, which is made up of Hock 

and Stockholm tar. MesHrs. Alfred Holt and Co., of Liverpool, 
take a very keen interest in the construction of lifeboats for 
their vessels, and they insist on blair being used for the piirpose 
referred to. 

One cannot expect to secure larch without knots, although 
when visiting an estate at Ardentinny, Loch Long, the writer 
inspected some timber cut from very tall trees whose branches 
were at a great distance from the groimd, and there waa hardly a 
knot to be seen where the material was cut, being magnificent 
specimens of the Scotch larch. Unfortiinately, the large bulk 
of the material which builders have to handle does possess knots, 
and these must be considered. Planka which have large black- 
edged knots must be taken out of the boat ; but within reason, 
knots can be dealt with by fitting doublings behind them and so 




I 



144 



SHIPS* BOATS 



arrani^ocl as to catch two timbers. These doublings should be 
w«'ll bedilt'd in thick white-lead paint and secured by copper 




soi,E:/Afc 



Fn;. ♦»7.- Section showing plank soleing. 

nails clonchod over moves. Thev must be fitted and secured 
bef(ne the. j)laiikinL^ is completed. (See Fig. 68.) 

Lairh is a very »:(K)d material for planking boats carried on 
vesst*ls eni:ai:ed in trades which do not take them through the 
tropics. It is resilient and touirh, but like wj'ch elm it needs to 
be closely fastened, as there is a tendency to warp. Turpentine 
is olitained from larch, so that the latter possesses certain natural 
(jnalities which protect the boat from the weather. 



fiij'J 



- ~x- 



.7"//V7^^/? 



r--r 






s- 



''>l^ 



-A 



O 
---♦•- - 



n/TA^Or 



o 



•^ ' ' ' ' ■ ' ' ' ....,.■■ 



k^'w 



PLA/^A 



A 



O I 



OOoBl/MSj 



U 



V^iuJ 




/'lA/y/r 



ELEVATION SECTION 

Fifl. (38. — Method of fitting doubling Whind knots in planking. 



The larger tlie tree tlic more brittle bix^omes the larch, 
although it will probably have a greater freedom from knots. 



i 



I 






CONSTIUICTION OF CLASS Ia OPEN LIFEBOATS H5 

ITiere is more resilience and etrengtli in a reasonable sized tree, 
although in the very narrow trees there is too much sap and 
the heart wood is not in mature condition. Old boatbiiilders 
constructing fishing-boats are always particularly anxious to 
secure " one-plank trees." 

Yellow pine and silver fir make very good boats, provided 
the vessels do not trade in climates of great heat. 

Boata are much lighter when built of these species ol wood, 
and they very quickly " take up " when placed in the wat«r. 

It ia qidte unreasonable to expect that material grown in 
northern or temperate climates will stand the extreme heat of 
the tropics. Sufficient experience from ships' officers and in- 
dpectors only goes to strengthen the suggestion, that lifeboats 
carried as a part of the statutory equipment of foreign-going 
vessels whose trade carries them tiirough climates of gre^it heat, 
should be constructed of mahogany or teak, and preferably 
the latter. 

The lifeboats supplied by Messrs. Caiid and Co. {now Mcsai's, 
Harland and Wolff, Ltd.), of Greenock, for vessels owned by the 
Peninsular and Oriental Steam Navigation Co., Ltd., have lasted, 
in many cases, for twenty years, or even a greater length of time. 
These boats are constructed of two thicknesaes ot mahogany, 
and, it ia almost superflnous to add, they were not completed 
under conditions of piecework. 

A specification may be complete ia every detail, and drawn up 
with the exj>ress purpose of ensuring that the boats are con- 
structed to the highest class, but imlcss the material has been 
thoroughly seasoned it onlj results in waste of money and 

The view point of the average boatbuilder is somewhat 
Ited 88 to the actual conditions of service of a vessel, 
so fat as they influence the life-saving equipment, and it is only 
the ahip's officer or surveyor who comes into contact with the 
difficulties and is able to secure the experience, that enables him 
to express an opinion as to what should be carried out to meet the 
actual requirements. 

The operation of planking is of the greatest importance, both 
in regard to quality of material and standard of workmanship, 
and it ia hoped in future that greater care will be exercised by 
those employed in the boat yards to prevent, as far as they are 
able, the necessity of a ship's boat, after it has been in service for 
three months, being covered on the inside with two or three coats 
of plastic or bitumastic enamel before it can be brought back to 




146 SHIPS* BOATS 

a condition of waterti^htness and fulfil the purpose for which it 
was constructed. 

As soon as the planking is in a condition to receive the 
timbers,, the inside surface is <^ven a good soaking coat of white- 
lead paint (without the application of a disproportionate amount 
of drj'crs), or boiled linseed oil. 

Timbers. — The regulation distance between the timbers, 
from centre to centre, is six inches. Sufficient reason has already 
been given for the necessity of preserving a high factor of safely 
in regard to scantlings. The comparison between the scantlings 
of boats coiLstructed under Admiralty supervision to a detailed 
specification, and those built to the requirements of the mercantile 
marine, will serve no useful purpose, as the conditions of service 
in the two cases are vastly different. 

The sizes of the timbers shown in Table XIV. are given on the 
assumption that they are w^ell rounded on the iimer surface. 
The section is considerably lightened without reducing the 
strength, and they can be workcxl into position with less difficulty 
than if the timber manitaincd a rectangular section. 

The position of the timbers are marked on the planking from 
the indications already given on the hog-piece, also those of the 
rising and the bilge stringer, to enable the sliver pieces between 
them and the timbers to be tacked in their correct position. If 
the gunwale is of the '* box " type, the tapered liner behind the 
sheer strake is also fitted in place. Care is taken to see that all 
doublings are fastened and clenclied. The planking is then in a 
condition to receive the timbers. The timbers at the ends of the 
boat are sj)aced slightly less than in., to allow for the flare-out 
at the gunwale, and tlit; heels of those which cannot be worked in 
one j)iece across the niithlle line are checked into the deadwood, 
as shown in the photograj>h of Fig. 4.*). 

Tinil)ers are usually made from American elm, owing to its 
close strainht i^rain and elastic nature. Oak and ash are also 
permitted, but the latter is trrated with suspicion by some boat- 
buildrrs jis being inclined to rot at the extremities. During the 
])eriod of the war certain substitutes had to be usihI for the 
ai)j)roved materials, but after tin' honn* timber supply had been 
organised there was little need for use of tlu^ substitutes, as far as 
th(» timbers were concerned. AVvch elm of straight grain was 
occasionally used, and also Jiome-grown English elm, but the latter 
wa,s more trouble than it wa^s worth, since for every timber 
secured in position two were broken and cast out. 

The extra cost of rounding the timbers is very small, as the 



CONSTKUCTION OF CLASS Ia OPEN LIFEBOATS U7 

process is quickly performed with the aid of the spindle machine, 
r>r by special cuttera inserted in the planin|f machine. A much 
lighter appearance ia given to the boat and the full faying surface 
of the timber is preserved. 

Timbers are fitted in one length from j.'unwale to fninwale. 

The operation of timbering ia usually commenced from aniid- 
shipa, working to the ends, so that those which are brolicu during 
the operation of bending may possibly be worked in at the 
extremities of the boat. 

The holes are drilled with the bit through the plank landings 
from the inside of the boat, care being taken, especially at the 
turn of the bilge, to keep the bit aquare to the surface of the plank, 
otherwise the timber fastening will be too close to the landing 
edge. With a ^-iu, landing there should be no difficulty. The 
nails are inserted in the planks in readiness for the timbers 
when brought from the steam-chest. 

The timber is usually secured at the centre of the hog-piece 
by a galvanised iron nail, and carefully worked towards the gun- 
wale. A fairly heavy hammer is used for holding on when the 
nail is being driven from the outside of the plank. 

Considerable divergence of opinion existed at one time as to 
the most effective means of securing the timbers. 

The common practice in most districts, before the standard 
instructions came into operation, so far as boats for the mercantile 
service were concerned, was to ply the vails over on the inside 
surface of the timber while the latter was soft and pliable. The 
method may be a successful one if the heads of the nails are not 
simk in below the surface of the plank, but it often occurs that 
before the nail has been completely driven home against the 
plank, the boatbuilder inside the boat has started to ply over the 
nail on the timber, and bends it in the operation, having used the 
same hammer as when holding on to the timber for the insei'tion 
of the fastening ; this practice is responsible for many split 
planks. If the timber nails are finally punched below the surface 
of the pl&iik they are either bent, nr the points lose their 
original grip of the timber, when the latter b in a soft condition. 

The method now in vogue throughout the United Kingdom 
is t4i clench all the timber fastenings over rooves in a similar 
fashion to the plank securities. The clenching operation, of 
course, camiot be done when the timbers are insei'ted straight 
from the st^am-chest, but there should be no need for tie " harden- 
ing up " process as previously explained. 

The method ot " rooving " the timber nails has always been 



1 



148 



SHIPS' BOATS 



considered to be essential for all high-class work, but where no 
p;overnin<5 specification is in operation, it is natural for the 
boatbuilder to take the " line of least resistance," and adhere to 
the " plyed-over " method of securing the timbers, which saves 
him the cost of copper rooves and a considerable amount of 
labour. 

TABLE XVI. 
Particulaus of OoFFica Nails akd Rooyxs. 



S.W.CJ. 



1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 



Diameter of nail. 



Fract.iuns of 
an inch. 



ft 

ifuU 

i 

i bare 

A f uu 

^]^ bare 

A bare 
■ i full 

i 

Jt bare 



])ccinials 
uf an inch. 



•300 
•284 
•259 
•238 
•220 
•203 
•180 
•165 
•148 
•134 
•120 
•109 
•095 



Blillimctnw. 

7 •62 
7-21 
6-58 
604 
550 
616 
457 
419 
376 
3-40 
305 
277 
2-44 



Diamotcr 

of roove. 

Indies. 



1'* 

i 

a 
n 

o 

iir 

A 
¥i 
U 
A 

i:i 
a" 



I 



Diameter 

of hole 

in roove. 

Inches. 



'324 
-324 
•276 
•276 
•252 
•252 
•212 
•185 
•160 
•160 
•144 
•128 
•116 



Thicknees 

of roove. 

L.8.O. 



12 
12 
12 
12 
13 
13 
15 
15 
16 
16 
16 
17 
17 



if done properly, as explained previously, the rooving method 
is much to be preferred, but if left in the hands of boys and girls, 
all it^ advauta^^es vanish, for a bad clench is inferior to a plyed- 
over nail. 

The timber nails are of a 8li«i:litly heavier gauge to the plank 
fastenings, and each nmst have a flat head. Reference should 
be made to Table XIV. for the correct gauge of nails to be 
used. 

Table XVJ. gives particulars of copper nails and rooves, 
showing the appropriate diamet^jr of roove tf) be used with the 
particular gauge of nail. 

Taking a Class I a lifeboat, witJi dimensions 26*0' X S'O' X 3-25' 
and 15 strakes of planking, constructed on the clinker prin- 
ciple, it is interesting to note that in addition to the fastenings 
in the combinations of the frame, such as stem, stempost, dead- 
woods, hog-piece, etc., some five thousand five hundred and 
fifty copper nails with the same num])er of copper rooves are 
worked in the planking, timbers, gunwales, and stringers. The 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 149 



total weight of copper nails in one boat of these dimensions is 
about 37 to 38 lbs. 

The writer has gathered a few particulars from information 
supplied to him by The Cartsbum Lifeboat Building Co., 
Greenock, which gives the approximate quantity of copper 
fastenings required in the 26-ft. lifeboat of standard dimensions. 
See Table XVII. 

All reference to cost of production has been carefully avoided. 
The best method of arriving at an estimate should be based on the 
cubic capacity of the boat. Five weeks is a reasonable length 
of time required for the constniction of a 26-ft. lifeboat of Class Ia, 
with two journeymen and one apprentice, working on time rates 
and without overtime. 

TABLE XVII. 

Approximate Number of Copper Fastenings. Open Lifeboat Class Ia, 

Clinker Build, 26 0' x 8 0' x 3-25'. 



Gauge. 


length. 


Inches. 


Inches. 


10 


^ 


10 


2i 


10 


3-3i 


12 


U 


12 


1 



Where used. 



Timbers. 

Garboard. and hood-ends. 

Stringers, risings, and gunwales. 

Planks. 

Scarphs. 



No. to the 
lb. 



110 
137 
80 
240 
300 



Quantity. 



15 lbs. 

2 lbs. 2 07.S. 

3 lbs. 

12} lbs. 

lib. 



Total number = 6550. Total weight = 34 lbs. 

Carvel-built Boats. — An alternative method of planking a 
boat is by working the planks edge to edge, having their surfaces 
flush inside and out, as illustrated in Fig. 55. The majority of 
motor boats and high-class pulling boats are constnicted on this 
principle or the double-skin method. 

A " carvel " built boat is stronger than a boat constructed 
on the " clinker " principle. In the first place it is essential to 
use a greater number of moulds, and in the majority of cases, 
they have to be prepared from the faired sections on the scrieve 
board. They are built up as shown in Fig. 70, and as soon as the 
combinations of the frame of the boat are secured together and 
erected, the section moulds are placed in position and well secured 
by fore and aft ribbands placed on the upper edges. 

It will be noticed that the moulds are made to the outside of the 
timbers. A suitable number of ribbands are fitted fore and aft 
from stem to sternpost, which gives the correct form of the boat 
at the inside surface of the planking. 



150 



SHIPS' BOATS 



The si^aatlia»B of tlie timbers can be reduced without detriment 
Ui the boat by a I in,, both inouldLxl aud sided, from the particulais 
given in Table XIV. 

The timbers are then steamed and bent round to the inside 
ol the fore and aft ribbands and temporarily secured to the latter. 

The outside surface of the timbers and the fayin^; edges of 
the planks are coated with white-lead paint as the work 
pronreaaos. 

Special care must of necessity be exercised in fitting the plank 
edf^es in order to preserve a watertight jouit. In fine work these 
are worked close together, but in heavier boats a alight chamfer 




is given to allow for a thread of cotton to be caulked into the 
seam. 

The motor boat in course of construction shown in the 
photograph at Fig. 142 waa timbered on this principle. 

Tlic planks ate secured to the timbers by copper nails cleiiched 
over rooves, one row at each edge, care being taken that when the 
nails are driven into tJie timbers the direction is such that it 
will have the tendency to close the seam. The process of clench- 
ing the fasteningis can be completed as each plank is worked. 

The usual precautions which must be observed in planking 
a "clinker" built boat, and already ejcplained in some dctaO, 
apply to a boat built on tlie " carvel " principle. With the former 
the timbers are bent when the boat is planked, and with the 
latter they are usually bent before the planks are worked. The 
practice varies in different districts, but the writer is inclined to 
tliiuk that a fairer boat is produced by the method described. 

As the planks are secured to the timbers, so the ribbands are 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 151 

removed from tlie moulds. The rubbers ftre usually fitted direct 
to the timber as shown in Fig. 55. 

Doable Skin Boats. — The highest class of motor or pulling 
boats is constnicted with two skins, having a waterproof fabric 
between. Provided the material is well seasoned and of suitable 
quality, there is no reason why the lifeboats should not last the 
life of the vessel. 

There are at least two methods of working the planking, but 
other methods will also be referred to when dealing with the con- 
struction of pontoon lifeboats and open lifeboats of Class IIa. 

The stronger boat of the two, when built on the double skin 
principle, has the inside and outside strakes of planking running 





^>!^^^^^ 



WATKIV ^^4>or LIMKN AC 



^ — -, — 




Fia. 71. Fio. 72. 

Methods of working tho planking of double-skin boats. 

at 45° with the keel, but each in the opposite, direction, so that 
the two skins cross each other at right angles. This method is 
illustrated in Fig. 71. 

The second method, shown in Fig. 72, consists of an inner 
skin with strakes of planking running aft at 45*^ to the keel, and 
an outer skin with strakes running fore and aft as in a '^ carvel " 
built boat. 

In both cases waterproof linen is worked between the two 
skins. 

Practice varies in diflfercnt districts throughout the United 
Kingdom. The writer will therefore confine himself to a brief de- 
scription of the method of planking a double-skin boat, constructed 
on the diagonal principle, which has come under his immediate 



SHIPS' BOATS 

ntitit-e in the yards of Messrs. Dickie and Sons, Tarbert, Loch 
Fyne, and Messrs. Caird and Co., Greenock (now Messi^. Harland 
and Wolff, Ltd.). 

Boats with small dimensions (up t^^i 22 or 23 ft. in leji^ith) can 
be constructed on tlie "diagonal" principle, having moulds 
built up as shown in Fig. 70, a description of which has already 
been given when dealing with " carvel " built boata. When it 
comes to boats of larger dimensions, the moulds are made of more 
Rubatantial material, and not of the us\ial " mould stuff." They 
are made to the inside of the timbers, and carefully checked with 
the lines on the ilfHir or scrieve board. 

The ram or frairu; i.e. the stem, keel, stempoat, with hog, 
deadwoods, etc., having been erectwl in position and made to 
plumb the keel-board, with the stem and stempost outwinding, 
the whole is rigidly secured to prevent any movement during the 
early stages of construction. 

The moulds are then placed in position, plumbed, and set up in 
conformity with the line of keel, stem, and stempost. The head- 
board is fixed and secured by shores from the overhead structure. 
The moulds, therefore, practically become fixtures, and are not 
removed until the boat is planked, tinibored, and gunwales secured. 
Reference should be made to Fig. 69 for an fllustration of the 
moulds referred to. 

Now comes the feature of constniction where practice differs 
according to the tastes of various builders, but the following 
is considered to be the simplest and best arrangement of planking. 
The moulds being made to the inside of the timbeis and fixed 
in position, good stout ribbands are worked fore and aft and let 
into and secured to the moulds, so that the outaide surface of the 
ribbands are flush with the edge of the moulds. The necessity 
for stout moulds is, therefore, obvious. 

We now have the longitudinal shape of the boat given by the 
ribbands. 

It is usually arranged that the deadwoods and aprons are left 
slightly larger than specified, to allow for their being trimmed 
fair with the lines of the boat. 

The timbers are spaced about 9 in. apart, and the scantlings 
equal to those shown in Table XIV. The wider spacing is 
permissible owing to the additional strength received from the 
diagonal planking. They are now steamed, fixed to the hog, and 
clamped to the ribbands until the gimwales are worked. The 
latter are aided and moulded to meet the specification require- 
ments and placed in position. 



CONSTRUCTION OF CTiASS Ia OPEN LIFEBOATS 153 

The gunwales may be solid or of the " box " type ; if the 
former is fitted, the timbers and inner skin of planking are usually 
checked into the gimwalc, with a good capping piece covering the 
gimwale and tlie upper edges of the outside strakes of planking, 
as shown in Fig. 79 c. 

The planks are now prepared and steamed, while an abundant 
number of small shores are placed at the disposal of the boat- 
builder and within easv reach. 

The inner skin is first dealt with ; these planks are worked 
diagonaUy at an angle of 45° from the line of keel. The upper 
ends lie aft, they are worked in one length from keel to gunwale. 
The inside surface is planed before working so that a slight touch 
up with a " flat scrape *' is all that is necessar}' to obtain a good 
inside surface on the completion of the boat. 

As the planks are worked they are secured to the hog, gun- 
wales, deadwoods, and aprons, with l|-in. spikes, sufficient to 
keep the planks in position, until the outer skin is fitted. 

The inner skin having been completed, a slight chintz of boat- 
cotton is worked in each seam in way of tlie hog, aprons, and 
deadwoods, this precaution being ccmsidered essential for 
watertightnesso 

The outer surface of inner skin is then coated with good white- 
lead paint and waterproof linen stretched thereon. 

The operation ol working the outer skin is commenced and 
performed in the same manner as the inner skin, except that 
the planks lie forward. 

The short shor(\s referred to previously are used for keeping 
the planks in their correct position before fasti^ning. 

The two skins are fastened together with copper nails clenched 
over rooves, the disposition of the latter being ascertained before 
the planking is commenced. The securities are completed as the 
outer skin is worked, being lined oflF by the person responsible 
for the boat. The outer skin is fastened to the hog, apron, 
stem, sternpost, and deadwoods with spikes or brass screws, 
and to the gunwale and hog-piece by clenched nails. Figs. 73 
and 74 show the general aiTangement of securities in way of 
the keel and apron of a boat constructed on the " diagonal " 
principle. 

From four to six floors cut from material grown to shape are 
usually fitted in the large pulling boats. 

Throughout the operation of working the two skins particular 
care should be exercised to avoid " pifffifig '' or " liolidays,"' i.e, 
there must be a perfect fit between the two faying surfaces. 



154 



SHIPS' BOATS 



The boat at this particular period of consinictiQn appears to 
be ill a condition of chaos, with shores inside, outside, and on top. 
These arc now all removed, and the boat canted in preparation 
for dressing or cleaning-oflE the outside. 

When working with mahogany or t«ak a slight countersink 
Ls made in the plank to receive the fastenings with the aid of the 
special " bit '' or " gutter'' and provided the tool is in the hands 
of a competent ])oatbuilder, the nails can be driven home without 
disfiguring the plank by using the heavy type of boss punch or 
" Mbjr 

It may be necessary to harden up the fastenings at the stem, 
sternpost. or heel seams, and the latter are finally caulked with 
boat-cotton and j)uttied by means of a " putty stick " which is 
shaped like an ordinary sharpened pencil ; the seams are thus 



,T I M 8 f: n 






"■'^"»^ .'«r«.K/| '':.']' /.r,s,o. '^vRA.e 







^ <^':>-^<< 



SECTION 
Fid. 73. 






PLAN 
Fio. 74. 



well filled and the work more efficiently completed than if the 
ordinary j)utty knifo were used. 

The foregoing remarks briefly describe the operation 
of planking a '* double skin '' boat, and as previously stated, 
different district's have*, varitnl nietliods or j)ractices, but the details 
ref<M'red to ai'c i'rnorjillv adhered to on the (^lyde. 

Rising. — Having described the methods adopted during the 
construction of the frame, and the skin or plankijig of an ordinary 
pulling ])oat of ( -lass 1a, attention will now be given t(j the various 
details associated with the internal fittings. 

The ** r/'.s' /"?///," or '' wmrimjy is the upper stringer which runs 
fore and aft from the stem to the st(M'n])ost apron, forming a seating 
for the ends of the thwarts and acting as a lomritudinal stiffener 
to the timbers, distributing the stresses which come upon the 
thwarts from the oarsmen or m<ast. 

The mateiial is usually of Ameri(?an elm or i>itch pine. Larch 
is unsuitable unless quite free from knots. It is fitted in one 




CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 



length. Between tlie timbers and planking tapered liners are 
secured, which provide a aolid bearin;; for the fastenings. 

The risinji is secured at every timber and to the planking by 
copper nails clenched over rooves and worked in red fashion. 

The scantlings should not be leiss than 1 in. in thickness, to 
provide a proper bearing for the ends of the thwarts and their 
securities, and not leas than 3 in. in width. 

The back of the riaiug, or faying surface to the timbers, should 
be painted hnfore being secured in position. 

If reference is made to Table XVIII. the rising can always 
be estimated to its correct position in relation to the gunwale, 
which will allow the thwarts to bo fixed at the standard depth 
below the capping-piece or gunwale, and the securities of the 
thwart knees will then centre the rubber and gunwale. 

The position of the rising ia illustrated in Figs. 87 and 88, 

Thwarts. ^The number of thwarts in a pulling boat is governed 
by its length, and in accordance with the following particulars : — 

LerlRth of Jift<boHt. Niiniber of thwarts. 

18 ft. and under 4 

19, 20, 21. 22, 23 and 24 ft 5 

25, 26, 27 and 28 ft 6 

29 and 30 ft. ... ' 7 

In order to keep the weight of persons down as low as possible 
in the boat, and yet not too low to make it difhcult to use the 
oars, the following depths from the top of the gimwale to the 
upper surface of the thwarts, have now become the standard 

dimensions to which most boatbuilders are working, viz. : — 

DiiittLDGe from t< 
of gunwale to U 
Length of bnot, ol thwart. 

26 ft. to 30 ft. (inclusive) 11 in. 

23 ft. to 25 ft. „ lOj „ 

16 ft. to 22 ft. „ 10 „ 

As soon as the rising is secured and the keelson placed in 
position the thwarts are cut to length, planed both sides, and 
attached tf) the rising. The scantlings vary from 9"XlJ' in a 
30-ft, boat to 8' X 1^' in a 10-ft. boat. The thwart in way ol the 
mast hasp is increaserl so that its width at centre is not less than 
that given in Table XIV. 

The materials nsed are pitch pine, red pine, Baltic redwood, and 



IV; 



SHIPS' BOATS 



'I'lulity IS ...ssftntial. Urrh Ls „,™'™^*-V Pulling boaSf^ «***» 

is U.0 narrow to allow the fnl br a^T.^,?"'* "^^^^t^^H 
ninninx inU, 8a,, wood H^Th^ ' ?''*'* *« b^ cu« JS?****" 

wl.,t« ,..,.«. .„t only the common spnferf^H 1"°* **»« A^ricif 
avoKl..! «.. .f. ,ui..kly Hphts when 'e^pii^t'^^ ** »>«^2ty 

\Vh<m the iinHimiuirf<»M»....i.i. r ., . " 



r.wiiy riii».i up iiiM) spimterH. "^^"^ weather and 

When th.! lUiHiipported lenirth of the thw«rf 

a HtandMon or p.Nar is fitt«l at the centre. 1^2,^?^.®^* '««t> 

th« keelH.,n an.| neeurcl t., the underside "Tth^ ^K^* *°P ^^ 

: >^ >y>»/— ir thwart, not 




A££iSO/V 



Kiu. 75. 





two screws 

!vf(>r 1(> tiike a dovetail clieck out of th 
w w.ll Mv vorfw..! .ui)i)oi-t. In this case 

" linylv. 

tlie thwarts, as it 
ippoarance t» the boat. 
T\\c (Ml,m»s of tin* Ihwiirts in any raso must bo rounded, and the 
o|HM'iition o{ liejulin.u iakos very liltle. il any, extra labour. 

With referenee \o the thwarts of a " square stem " boat 
Iho same regard should be paid to the number approved to be 



CONSTRUCTION OF CLA8S Ia OPEN LIFE150ATS 157 

fitted in accordance with the length of the boat. The stern-sheets 
are of greater length than the usual distance between the thwarts, 
and as the stern seat is very wide to allow the gangboard to be 
fitted so as to take the lifting-hook, one of the thwarts, which 
is included in the regulation number, is fitted under the seat, 
with the usual single knee. The rising is fitted from stem 



- - .^^wiyALk 




ELEVATION - 




Fio. 70. — Mctliod of lilting benchcM in u "square-stem" boat. 

apron to tniiLsom, and secured at every timber. The gang- 
board aft is fitted in a similar way to a double-bowed boat, 
the upper surface being kept flush with the stern benches by 
recessing the gangboard over the thwart and securing the two 
together witli three screw bolts. 

In a Class III. boat, where it is not necessary to fit side 
seats forward of the second th^\art from aft, the after thwart 



158 



SHIPS' BOATS 



is uHually let into the imiv^ to allow for the fitting of the after 
side seats. In the same type of boat, i.e. an ordinary open 
pulling boat without buoyancy air-cases, it is invariably necessary 
to fit side seats to provide for the full accommodation, but in 
a " jolly " boat, which does not form part of the life-saving 
equipment of a vessel, and where side seats are not fitted, it is 
either necessary to increase the depth of the knees by an inch 
beyond the dimensions shown in Table XVIII., or to lift the 
rising one incli. 

Fig. 76 illustrates the method of fitting the benches and after 
thwart in a boat with a square stem. 

The fitting of a simple vertical tie board from timber to timber, 
under the stern benches, is more ornamental than useful, and 




PLAN 
Fig. 77. — Quaifcei knees. 




U^^eft ST/fAKK 



_^!KMCf 



B/AfOiAfC SrWAiCF 



ELEVATION 




^^'iG. 78. — Quarter badges. 



shoukl be avoided, as tlieie Ls little or no supi)ort given to the 
liftint'-hook. 

Quarter knees arc iiltt.'d lK*t\v<M.*ntli<^ gimwalrs and the cross-piece 
attadicd to thti tmnsoin of a scjuaro-steni boat. The arrangement 
is illustiatcd in Kig. 77. These r(M[ui!e very careful fitting and 
must be cut from .selected material iirown to shape. A check is 
taken out of tlie cross-[»ieee. and sometimes also from the gunwale, 
to prevent movement and to inciease tli(^ efiieieney of the security. 
The fastenings are of stout copper rod clenched over washers. 

The stem and sternjmst knees are fitted to strengthen and 
protect the gunwale and upper stiake, but unless they are sub- 
stantially se(;ured tlicy only become useful for onia mentation. 

Gunwales. — Tlie consensus of o])ini()n among boatbuilders in 
regard to the most satisfactory type of gunwale leaves no doubt 






CONSTKUCTIt>N OF CLASS U OPEN LIFEBOATS 169 

ill the minds of practical men that the " box " form is the 
strongest means of construction for all types of boats. 
m The general arrangement of such a gunwale b shown in 
|jig. 79 A, 

It will be noticed that the timbers are carried up to the upper 
etlge of the inner gunwale or " inwale," and sheer atrake. 

Before timbering, a hard wood filling piece is fitted between tlie 
sheer strake and the timbers, fore and aft, tapering from the full 
thickness at the lower edge to lialf the thicloiess of the binding 
strake at the upper edge. By tapering this filling piece, tlie 
fairness of form is maintained in the boat. The effect of fitting 
a filling piece of parallel section has the tendency to throw the 
gunwale outboard, which gives an unsightly appearance to the 
experienced eye. 

The inner gunwale is usually of American njck elm, varying 
from 2J in. to 3J in. moulded, and I in. sided, and is fitted in one 
piece from stem to stempost apron. 

The upper or sheer strake is not less in thickness than ^ in. 
greater than the planking. The breadth is an'anged to suit the 
position of the rubber to enable the throat bolts connecting the 
thwart knees to be fitted well down towards the side benches. 
These breadths can be secured by reference to Table XVIII., and 
should be continued for about two-thirds the length of the boat, 
gradually tapering towards the ends. 

The inner gunwale and sheer strake are secured to every 
timber by copper nails, clenched over roovea, and placed in " reel " 
fashion. 

Care should be taken before fitting the combinations of a 
■' box " gunwale to see that all faying surfaces and heads of 

[timbers are well coated with white-lead paint. 
SoUd chocks of hard wood are fitted between the timbers in way 
of the thwart knees, breast-hooks, and crutches, so that between 
Old sheer strake and inwale, with the exception of these chocks 
and the capping piece, there is left an open space which ventilates 
the gunwale. 

Those chocks should be of selected hard wood, free from 
sapwodd, and well secured in position. Odd pieces of material 
lying about the boat-yard ubould be discarded, as the writer has 
repeatedly seen evidence ()f timbers rotting at their heails and 
tunning down to the bilge, resulting from the use of unsuitable 

Ctnatjirial, and there was no alternative but to rip the timbers out, 
t is a difficult operation in boats fitted with a "box" 
ale, and one which does the planking very little good. 



fi 

I 

I? 



SHIPS' IJOATS 





aJterniillvE method. 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 16" 

Some shipowners prefer the open " box " gunwale, i.e. the 
omission of a capping piece. Such an arrangement has the 
advantage of providing a good hand-hold for gaining access into 
the boat from the water, but it leaves the end grain of the timber 
heads exposed to the weather, which is considered a disadvantage. 
In good-class wooden saihng vessels all exposed end grain of 
btem and sternpost heads, bulwark stanchions, etc., are covered 
with sheet lead. 

The Ht-andard practice in most districts is to fit a capping- piece 
about I in. in thickness for the full length of the f^unwale, and well 
secured to tlie inner gunwale and sheer strake by brass screws. 
It is usually fitted in two lengths in large pulling boats, and if the 
boatbuilder steams the material and directly bends the capping- 
piecc into position, he is asking for trouble. 

In most yards an iron mould made from a channel bar is used 
for bending the cappiug-pieces after steaming, which are wedged 
in this position for a day or two. The material is then in a con- 
dition to be easily worked, and proper fastenings can be inserted, 
otherwise, if steamed and worked immediately, the builder 
is in such a desperate hurry to get the capping bent at the ends, 
that the sti'css on the material is too gre-at, and if it does not 
split about sLx feet from the ends during the operation of bend- 
ing, it eventually may do so after six weeks of exposure to the 
weather. 

Provided the inner gunwale and the sheer strake are not 
touched when making provision for the insertion of the crutches 
th rough thecappiug-piece and chocks between the timbers, it seems 
ineceaeary to fit cheek pieces to the " box " gunwale in way of the 
crutches. A good stout plate should nevertheless be fitted on the 
face of the capping-piece, secured with four stout screws, and not 
I the usual fitting, about 2 in. in length and 1^ in. in width, which 
s sometimes fastened with two French nails, 

There is a saving of material in working tlie " box " giuiwale 
' ic comparison with the " soLd " gunwale, and when the employees 
|i bwiome accustomed to the method it does not cost more than 
I thirty shillings extra in a 20-ft. lifeboat, 

An alternative method of forming this gunwale is sJmwn in 
[Fig. 79 D, which the writer is inclined to consider as a " mongrel " 
I type. It is neither the solid nor the box form, and possesses the 
I disadvantage of leaving the upper seams exposed to the weather, 
rand eventually water may find its way between, giving an 
Vopportunity for the timber heads, which cannot be seen, of 
Fitecoming afiectcd with wet rot. 



162 SHIPS' BOATS 

This method is not recommended, and is considered inferior 
to tlie ordinal}' and " open " type of " box " gunwale. 

The solid gunwale is usually fitted in pulling boats of 23 ft. in 
length and below. Fig. 79a illustrates the details of this combina- 
tion. The timbers form no comiection with the gunwale. They 
are each cut short to allow the solid gunwale to have a full faying 
surface on the sheer-strake. 

The box gunwale is more resilient than the solid gunwale, 
and transmits the stre-sses through the timbers, and are then 
equally distributed over the hull. This question is of consider- 
able importance where boats arc launched from davits situated at a 
considerable height from the water, and the possibility of the boat 
coming in violent contact with the ship's side during the operation 
of lowering. 

Numerous cases have occurred, especially when the thwart 
knees were not secured to the rubbers, where the boats have 
bumped into the shell-plating or obstructions on the side of the 
vessel, and the solid gimwale having no contact or security with 
the timbers, caused the upper strake to split, and immediately the 
gunwale became useless. The photograph shown in Fig. 107 is an 
illustration of what actually occurred to a ship's boat when being 
lowered in a hurry under difficult circumstances. The upper 
strake split in the manner described, and the gunwales were, 
therefore, of little use, consequently the breast- hooks were broken 
and the whole of one side of the boat came away from the 
apron. 

It is a waste of the reader's time to make any further com- 
parison between the two types of gunwales under review. For 
any type of open pulling boat wiiich forms a part of the statutory 
equipment of a vessel, tiie solid gunwale is considered a dangerous 
fitting. The writer may have been unfortunate in his experience. 
but sufficient has been seen by him from actual results to make 
him express definite views on the subject. 

Solid gim wales are fitted in one piece, care being taken to 
obtain tlie correct bevels of tlie upper strake, to allow tlie up|>er 
surface of the gunwale to lie in a horizontal ])lane. It is usual 
to steajn the gunwale and clani[) it round the outside of the 
upper strake overnight, in readijiess to secure in place tlie 
next day. 

There are two common methods of ending the gunwales at the 
apron, as illustrated in Fi<is. 8<.) and 81. 

The first method siiows the end of the gunwale cut off with a 
square butt and checked into the apron. The second method 



I 



CONSTKUCTION OF CL.iSS Ia OPEN LIFEBOATS 163 

provulea for the enct of tlie gunwale to be cut at a bevel to siiit the 
back of the apron. There is little to choose between tha two 
practices, it being a matter of individual ta«to ; but that shown 
at Fig. 80 has the advantage, that wlieu the gunwale receives a 
bump, the effect is felt on the apron and not on the upper strake, 
which is worth considering when a solid gunwale is fitted, 

A rowlock was originally meant to be a row-lock, and cut out 
of the upper or wash strake to take tlie oar, and when the boat was 
under sail the rowlocks were filled in with portable j^pj^fs and 
attached to the boat with lanyards. Rowlocks are not often 
seen in pulling boats for the mercantile service, having been 
replaced by criUdies, aad the latter are now generally referred to 
as rowloclra. 

Provision muat be made for the loss of strength in the aolid 





Fio. 80. Kiu. 81. 

Piuiis p( eliding suliJ gunwulu at apron. 

gunwale, in way of the crut«h holes, by fitting check piexa aboiiF 
10 in. in length and the full breadth of the gunwale, well secured 
to the gunwale and upper strake by copper fastenings clenched 
over rooves and screws, as indicated in Fig. 82. 

The depth of the gimwale la not sufficient to adequately 
support the shank of the cruU-h, which makes it necessary to fit 
toe cleatu, hnniodiatcly below the j;unwale, as shown in Fig. 82. 
Each crutch is well secured by a chain lanyard to the boat. 

The crutch holes, after being drilled, are burnt out with a hot 
round bar of iron ; this prevents the wood from swelling and 
allows the crutch to be always inserted without difficulty. 

The material of the solid gunwale may be of American elm, 
oak, or ash, and it is well secured with at least four clenched 
fastenings between each pair of thwart knees. 

An improvement can be made on the solid gunwale by 



'^:j- 3..4^ 



- _. 


• ■ — *-* ^ 


1 


• • ^ . ^ 


w ; 


P m 

* • 


a . 


^T'..' 




Tl- :-.. 


w 


1. .^^. ; 


^L• 


'- .: '.-. : 




H . w.. v^. 


i:n 


<r r, 1 



• « • 



^ • 



- — • 






-^ job. bnt ejM. 
- *^t? other. I 







- L-EI « A- "^s _ 

— ^ ^ 






_ -. .y..-. /\i». .-. 




I CONSTEDCTION OF CLASS Ia OPEN LTFEBOATS 165 



I 

^M in as loog leagths as the breadth of ttie material will allow. It ia 
^K usual to secui'o these lengths in oue breadth. The material nmy 
^K'lie of pitch pine, yellow pine, teak, or red pine, f'ypress quickly 
^H'dtiinks ; Oregon pine, when cut into small scantlings splits and 
^r opens out with the effect of warm weather unless coated with 
oil immediately after workin;;. Giood resiilta have been secure*! 
from the use of well-seasoned Califoraiau redwood, hut it has 
the disadvantage of ahowin^ everj- impression made on ita 
surface, 

Sufficient experience has been gained with the use of white 
[ pine and Scotch fir during the period of the European war, when 
I timber substrtutea were permissible, to recommend that these 
I materiahi are unsuitable for the purpose. 

The common method recently was to scarph — or to make an 
I attempt at scarphing— the aide seats with the thwarts. ' They 
1 are now fitted in continuous lengths above the thwarts and nm 
f'from stem to sterapoat apron, 

Tlie "deck " ends are worked from the first thwart to the 
[ stem, and from the last thwart Ui the aternpoat. The centre por- 
[ tion, or garu/boanl, ia made of the same material and scantlings 
I as the thwarta. A common, practice is to slightly check it over 
I the thwart and well connect it to a ledge chock attached to the 
I apron, a cross-piece let into the rising and bolt«d to the thwart. 
I Tliis provides a rigid coruiection for the securities of the lifting- 
[ hooks, which is such an important factor with a lifeboat filled 
rwith a crowd of passengers, probably numbering fifty, and 
|.«winging in mid-air at a distance of thirty feet above the 
I water. 

Fig. 83 illustrates the method of fitting the gangboard and 
" deck " ends. 

Where double knees are fitted, the lower palm connecting bolts 

I afficiently secure the side benches to the thwarts, but in tlie 

Me of single knees, it is usual to arrange the butt« of the side 

ftttenches welt clear of the knees and bolt the former to the 

p til warts. 

To provide the proper seating, accommodation for tJie total 
jQumbor of persons assigned, it is necessary in lifeboats of 21 ft. 
jin length and upwards, to fit loicer cross seals. These are made 
Iportable, so as to permit wounded persons being placed at the 
[bottom of the boat, if necessary. 

Lower scats aerve a double purpose and can be used as 

(stretchers. The supports are made out of English elm or other 

niitable hard wood, about L in, to 1^ in. in thickness, and secured 



Boi 



INSTRUCTION OF CLASS Ia OPEN LIFEBOATS 167 



Thwart Knees. — The thwart kneea are now usually made of 
wrought iron, owing to the diificulty of securing a continuous 




1 




mm 




n. 85. — DooWe wooden kncps. 



Fin. : 






{rnltu kTioc 



iPPP'y "^ wood knees, which must be cut from material j^own to 
'lape. 

Larch roota make good knees for the small type of puUinj; 
lats. English elm and oak kneea must be securtMl from well- 
loned wood, giving a proper crook, and sided t4) IJ in., other- 
fee Uicy are of httle use and (juickiy split from the cf^e 



168 



SmPS' BOATS 



\ 



tJie weather. The securitiea must be of ccipjier or galvanised I 
iron with good clenches on rooves or washers. Wire nails are not I 
permitted for the purpose of aecurity. 

Where double wooden knees are fitted, it k usual fa> secure s 
pad piece, or chock, between the kneea, as illustrated in Fig, 85, I 
tapering off to nothing at the toe and heel of each knee. This ! 
method adds strength and support to the knees, and is certainly I 
an improvement to the ordinary type of wooden knee. 

The scantlings of knees are detaUed in Tables XIV, and XVIII. I 
The usual practice b to fit wrnught-iron knees, Jumped or 




Fio, 87. — Half seotioQ of Clasq Ia Ii 



welded knees are not permitted, they should be of substantial ' 
section with at least IJ in. of material at the throat. The iaatca- ] 
ings are arranged so an to obtain the greatest amomit of aecurity ] 
in co-operation with the combinations in way of the gunwale ; nut 
and screw bolts are usually fitted for the purpose, the upright arm J 
having one security through the centre of the gunwale, timber, | 
or chock, and upper strake, and another through the hardwood \ 
chock, binding atrake, and rubber, the nuts being on the upper 
arm of the iron kniee with the bolts lightly clenclied over the 
nuts. The securities in the horizontal arm attached to the side ] 
benches or thwarts are generally three in number, the centre one 1 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 169 

being a stout screw, aud the other two. ordinary nut and screw 
bi)Ita ; but iu this case the nuts are placed on the undereide of the 
thwart and sci-ewed up on atout washers, with the pointe of the 
bolts 8li;fhtly clenched over the nuts. If the nut« were secured 
on the horizontal arm of the knee, they would be a source of 
danger to men runninf? alonjr the side benches, and tend to throw 
them overboard. It ia iiaual to lit a protectinj; strip of wood, or 





»I5« 


1 




i 


i .,;.,».„„, 


t„ 


,^'l{ .u..-iV..„ If ' 


rl -Ui"!':' 1 




r' 



Fio.8 



— Methiicl of lillirif! thu-nrt knccri mid sitta bencliea. 



liataoM, attached to the thwart, to i^eep the buoyancy air-cases off 
the nuta. 

Fig. 88 shows the details of the securities for iron knees of the 
ordinary pattern. 

Table XVIII. has been drawn up to simplify the work of the 
boatbuilder and smith ; if the various dimensions are adhered to, 
the combinations in way of the ^iimwale will be so placed as to 
always allow the securities to coincide witJi the holes already 
drilled by the smith in the thwart kniee. It often prevents the 
bolts being inserted at a great bevel, or missing the rubber 
altogether, and necessitating the bolt being secured to the binding 
or upper strake. 

Single knees are permissible in boats of 24 ft. in length and 
under, but it is the general impression amon^ boatbuildera and 
otherH that this is a very prominent weakness in the present 



♦ . ^*v* 






"■^ >■. '..'.T ' ■. ^=?^-* I 



- 'f 

1 . 



"r 






. ' :"::_r z >.-e 



■ , • ' / " ■. It...... 



:> i:.r:->o are 
- :>:v -:ii-::o or 



CONSTRUCTION OF CLASS Ia OPEN UFEBOATS 171 

double, so as to be of some substantial support to the com- 
binations. 

WKen single knees are fitted the scantlings are increased. 

A concession has recently been granted to fit knees of convex 




iron, f in. in thickness, in boats of 24 ft. in length and under. No 
reason is seen for lowering the standard in this respect. This 
practice was never seen by the author in yards of good boat- 




I '^ 

«'f' I I ; 

1 (o/ \ol I 



SECTION PLAN 

Fro. 90.— DotaiU of Hornby's patent knee. (No. 10,704.) 

builders, but it naturally follows that the competing finns will 
be guided by the minimum standard. 

All iron thwart knees must be galvanised. 

Id lieu of the double iron knees, a special type of wrought- 
iion single knee liaving double palms, is sometimes fitted. The 



172 SHIPS' BOATS 

upper or vertical arm is hooked over and well fitted to the gunwale 
and sheer strake. The horizontal arm has double palms which 
are securiMl to tlio thwart. An illustration of the arrangement 
is shown in Fiir. ^^<). 

To provi<lo ef!i(i(»nt soturitios for the reasons previously given, 
these double palm knees should be so designed as to allow one 
of the bolts to pass through the rubber. There is certainly a 
saving of weight with this type of knee, but not very much 
advantage is gained in cost. The greatest care has to be exercised 
in making each knee fit at the gunwale at the particular thwart, 
to prevent the nece-ssity of fitting filling pieces. 

A very elHciont type of single knee having double palms, is 
that which has boon patented by Mr. Hornby, of Seacombe, near 

Liverpool, the details of 
..^^s^jr^A^^ V . which are inven in Fig. 90. 

A il^ ^ . V - -r^^>^v The dmerence between 
/^f''^ '' •^6£^s this method of forming 

''^\/ the knee and the approved 

z"^^- -'^ ^ .^ , ccmvex pattern is verv 

^^^'^^^ \ -^ marked. 

^ ^ ij'^ ^ Breasthooks and Floors. 

surr J; -?* — Ref (jrence has already 

,,. r.,/>/>//yd^ <i >'^ \^^^^ nx^A^ to the neces- 

sity of providing efficient 
combinations at the ends 
r^'' of boats to meet the 

Fkj. 01.- -Plan of upprr broaMlKM.k. heavy stresses which come 

upon them from the lift- 
ing-hooks, (»tc. Stout })reastlio()ks must be iitted at the aprons 
and gunwale eiuis ; the securities of which are similar to those 
of the tliwart knees, having a throat bolt which passes through 
to the face of tlie stem or sternpost. (Sec Fig. 91.) 

When made of wrought iron, the breasthook should be of 
substantial thickness and not loss than \\ in. at the throat. 
The use of cope inm shoukl be entirely avoided. 

Wooden breasthooks are cut from material grown to shape. 
Lifeboats over 21 ft. in length must be fitted with an upper 
and a lower breasthook, both at the stem and the sternpost. 

\Vh(»n the lif(»boats are lifted from near the ends, as with the 
Welin davits, a lower breasthook, or deep floor, is essential in 
all boats, irrespective of length. 

This lower breasthook is fitted midway between the deadwood 
and apron scarph and the upper breasthook, and is usually 






C"JX=»'''V. 



( nNsTIM"( TlOX OF (LASS Ia oPKN LIKKi;().\Ts i 



I • » 



!ii(«ii {>Miatr([ witli till' emliiiLi <>t tlic l)il;jr si liiinci-. ( Jiuc'k.s liriiiu 
lit ted between tlie timbers iii wav of tlic iron breasthook. (Sec 
Fi-. 92.) 

The writer lias a preference for a good stout wooden breasthook 
with a throat bolt well secured to the face of the stem or stempost, 
and having arms of sufficient length to allow for through fasten- 
ings at two of the timbers, on each side of the boat. In this 
case the breasthook is checked over the timbers and just touches, 
but doe> not unduly bear hard on the planking, the full bearing 
being taken by the timbers. Care must be taken to fit wedge- 
shaped liners, or filling pieces, behind the timbers in way of the 
breasthook to prevent the planks being drawn at their centre 
and splitting. 

The fitting ol floors at the ends of a boat depends on the type 




3/lC£ Sr^fdVG£-4f 



//ra/v 3^£'AsrHOO^ 



SreM 



S^£ASrMOOA 






Fio. 92. — Plan of iron lower breofithook. 




r/ArB£A 



Fig. 93. — Plan of wooden lower 
breastliook. 



and position of the lifting-hooks. Provided the timbers have been 
checked into the deadwood, it is usually only necessary to fit 
one deep floor at each end of the boat, near the lifting-hooks, 
checked over the keelson and incorporated with the timbers. 

When the timbei*s are not checkeil into the deadwood some 
specifications insist on floors being fitted at every third timber 
which does not cross the deadwood or hog. 

The working conditions of the smaller type of coasting 
steamer, paiticularly in regard to trawlera, make it necessary 
for their boats to be constructed on lines which are suitable to their 
requirement«, and it is usual to iit a heavier form of hog and 
dispense with the keelsoji, as the latter would interfere with the 
usefulness of the boat. Good stout floors are fitted at the ends, as 
the boats are usually lifted on board with a wire sling. 

Rubbers and Anti- fouling Arrangements. — Rubbers are usually 



174 SHIPS' BOATS 

made from ^Vmcricau elm or oak, in half-round or pear-shaped 
section, and extend in one piece for the full length of the boat, 
being secured to alternate timbers with copper nails clenched 
over rooves. 

The feature of these rubbers is not only to form a protection 
to the gimwale, but an excellent longitudinal stiffener is provided 
when associated with the thwart knee securities. 

It is considered that it would be an advantage to the boat to 
increase the scantlings of the binding strake, owing to the number 
of heavy fastenings which pass through it when securing the 
life-line rings and rubbers. 

Where boats are not fitted with a rope fender or outside cork 
buoyancy, the lower edges of the planks of clinker-built boats, 
from the binding strake down to the turn of the bilge (usually 
about the fifth plank below), are fitted with tapered filling pieces, 
for a distance amidships, equal to one-half the length of the 
boat. Vertical rubbing pieces may be fitted if desired, but 
the usual practice is to fit the horizontal strips and secured to 
the timbers. 

The purpose of these filling pieces is to protect the plank edges 
and landings from damage, should the boat come into contact 
with the ship's side when being lowered overboard. 

Care should be exercised in fitting rubbing strips to give 
them a neat rounded section in order to preserve a finished 
appearance on the plank edges. 

Bilge rails are not required to be fitted by the standard 
regulations issued by the Board of Trade, but they provide an 
excellent handlioid for persons stniggling in the water, and should 
the lifeboat be capsizetl, they become a ready means of assistance. 
Tlie details of fitting the rail below the turn of the bi}ge is shown 
iu Figs. 9-1 li and o. 

The position of the rail at the bilge should be such as not to 
foul the ship's side when tlie boat is lowered. 

it is secured t^) the planking and alternate timbers by stout 
screws, care being exercis(*d to prevent the fastenings from 
[uercing the full thickness of timber. 

The Peninsular and Oriental Steam Navigation Co., Ltd., in 
their double-skin lifeboats, have an upiMir Juuid-rail, or jackstay, 
fitted at the gunwale. The arrangement is illustrated in Figs. 79 c 
and Dl a. The life-lines are secured to the gunwale rail. The 
relative positions, of the bilge rail, life-lines, and gunwale rail, 
provide every facility for persons obtaining access into the boat 
from the water. This has been a standard practice with Messrs. 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 175 

C^ainl and Co. for many years, aad ia a considerable improvement 
«u the arrange nieiita usually fitted in ships' boatA. 

An efficient form of protection to the transom and plank 
codings in a " square stem " boat is given by the fitting of 




.PiAJVK/fVC 



m 



J) ^ ' ■ 






S /?A/*- ^^ 




A, iilnn of jiirkKtay or uuawiilg rail. 

». Irian uf<<URcr*ll. 

v. Mti-tluii n[ lilbn rail. 

I>, metliiHl ol llttlDK lUg-Une rlufl*. 



quarter baAjes, illustrated at Fig. 78. They are made of hard- 
wood and secured to the fashion-piece, gunwale, planking, and 
rubber. 

The necessity for the provision of rope fenders in all lifeboats 



SHIPS' BOATS 



is obvious to persons wlio have hod any piactjcal oxpeiieoce io 
the operation o( launching I>oata under difficult circumstances. 



mpJiL scfCM n 




iiAW 

SECTION 

Vm. ys.— Coir rci|H' fi-uiicr filtvd to moiliiicil ClsM Ua lifeboat. 

Hand fcndei'B are cuii^iclcred very objectionable, and in all 
f<robabi))ty would be found itiisHing when required. 

A 7-in. rope fender 

_P would certainly limit 

the riak of damage to 

>«J^£ the hull of a boat if 

ellieiently secured im- 

' ' ,.■ , ;.f^*„ mediately under the 

\ .' ■ '■vi '■(■ysj-zr rubber. 

^— j These fenders 

^ should be j-ieldiuf^ and 

^ ~ resilient, and if coir is 

used it should coQsi£t 

of long strands as a 

rule, uulaid, but 

marled to tiie necee* 

Mjiry diameter, and iu 

no case should the fen- 

■ der be less than 4 in. 

l''io. ii(i.— Jfojit ItiiUiT u> iiii.iur Ixiiit. <-'oir rope is made 

from the libres of the 

oi-dinuiy hemp rope, and 



w 



cocoamit tice, is much lij^htiT than the 
about equal in Mlu'iii;th. 

Fiji. "■> shows lln' iiieOidd of littiny coir rope fenders to the 
iiLoditied Class Ua lifeboats. 



CONSTRUCTION OF CLASS 1a OPEN LIFEBOATS 177 

Another methoil sometinieB adopted as a means of pnitectint; 
motor boats is illustrated by Fit;, ^*h ^^*^ consists of a number 
of strands of rope made up to tlie required diameter, secured to 
tlie timbers by strong wire. 

Padding Rentiers are made up from old rope, unlaid and served 
with apunyam to about 6 in. in diameter, covered with canvas 
and painted, or with rope mattinsi. Fig. 97 ilhistrates the 
method of securing these fenders. The pudding's and the life- 
lines are attached to a coir rope from 4 to 7 in. The mcoaurenient 
of the rope is taken around its circumference. 

It is easential that the loops of the life-lines should be kept 
parallel to the L.W.L. 

There is a diversity of opinion as to the relative value of the 




^L tlie 
^B euffi 



Fio. »7.— Puiiiling (endprs and life-li 



pudding fender as compared with the ordinary coir rope. WTien 
the boat conies into violent contact with the ship's side the 
stress is partially taken by the pndding fender, but transmitted 
to one particular portion of the gunwale combination, whereas 
it is considered that with a large continuous rope fender, the 
stresses would be distributed over a wider area and local damage 
would be avoided. 

The writer's exjierience is that the puddings very quickly 
get damaged and need constant attention and repairs. 

When lifeboats are lifted at the ends by the Weiiii quadrant 
type of davit bracket, also the Martin or McEkchnie patterns, it is 
necessary to substitute two thicknesses of reinforced rope, in lieu of 
tlie pudding fenders at the stem and atempost, tu allow for 
eufficient clearance at the davit frame. 



178 



SHIPS' BOATS 



The Board of Trado have recently isaued a circular, No. 1606, 
reeomniendinf; that where {langeroiis fittings are already fitt«d 
(in pxistinf; nliips below the boat positions, action niiiBt be taken 
U> modify tlie.-c pn)jcctiona, or fit special fore and aft coir fenden 
not lesx tliaii 4 in. in tliameter. and secured under the nibben 
of the boatn. In addition, three vertical rubbcrB are to be fitted 
aroi<lRliips mode up of homp rope, tapering from 3 to 12 in. in 
(-ireiinifen-Ji(-e, the thickest portion of the rubber protecting the 
}iil}>e of the boat adjacent to the ship's side. These midship 
rulibors are to be weoured from gunwale to giinwale. 

Anipbt pntt^ction is thiut provided when the boat is being 
h)W<Te(I from a vessel having an adverse list, and to meet the 
contmgencv when it is thrown against the ship's side by a 
heavy sea when afloat. 

Tank CleadlnE. — Tlie front casing which encloses the buoyancy 
air-tanks is worked in short gates between the thwarts, 08 illus- 




Vi' 



ELEVATION 
-Mctlind of littinj; tiink ck'niling. 



trated in Vi}". OH, and made up of narrow " vced " pine of J in. 
to ^ in, tliick. ti<Hid Mt<mt olan)]Uj arc fitted to the portable 
p()rti(ins of tlic casing to enable tJie toiiks to be periodically 
inspected witJioiit damaging the cleatiing. 

.Solid supports at least J in. in thickneea are fitted under the 
thwarts, and setmrcd in place in such a manner as to be of some 
substantial help to relieve the weight on the thwart. 

The cleadiiig is held in |>ositiou by an inner and an outer strip 
of wood naming fore and aft at its lower edge. Some firms 
utilise the bilge stringer for this purpose. Consequently, the 
stringer is fitted in such a position as to give the minimum 
amount of support to the bilge, A portable securing strip, 
made of teak or other suitttbie hard wood, and rounded at 




PeONSTRUCTION OF CLASS Ia OPEN YlFEBOATS 179 

I its upper edge, elieck«l at tlie thwarts and butted at their cpntres, 
1 hol<b the upper edge of the cleadinft securely in position, gives 
I a neat finish to the boat, and provides the quickest means fnr 
I removing the Imoyancy air-tanks without dama|j;ing the cleading, 
[ The cleadinK front is kept flush with the side benches by the 
I fitting of an inner upper ledge. The portable securing strip la 
\ attached to tlie side benches with button-beaded brass screws. 

To provide for easy withdrawal between the solid siipporte 
L under the tbwarU, buoyancy air-tanks should not be more than 
I 3 ft. G in. in length. 

Attention must be paid to the mctfiod of fitting the cleading 
I in the stern and head sheets, in its relation to tbe floor-bfiards, to 
I enable the former to be easily removed without diffictUtj-. 

The whole of the arrangements 8h(iuld be of a substantial 
character, to enable the buoyancy taniis t« be inspected and the 
planking behind periodically painted. 

Some form of protection is given to the air-casea from the 
copper clenched naila in the timbers by securing their wooden 
I strips to the face of the timbers as shown in Fig. 89. 

Rudder and Steering Arraagements.^lt would almost appear 
I auperfiuoiis to state that the rudder should be of ample strength 
\ and siutable in •^orm, but esperionce proves the necessity of 
I inserting full particulars in the ai>ecification9. 

The material must be of a tenacious character, not easily split, 
pith a thickness varying from 1 in. to 1} in. English elm serves 
the purpose as well aa any wood. The rudder ia worked in one 
piece, the lower edge being protected with a toe piece and secured 
by spikes. The upper portion is strengthened by clieek pieces, at 
I least } in. in thicloieas, carrie<l down below the upper pintle, and 
I worked with an oval section. 

Fig. 99 shows the rudder attached to a 2fi-ft. lifeboat of 
IClass Ia, and Fig. 100 illustrates the type of nidder fitted to an 
|18-ft. dinghy. 

The cheek pieces should be well secured to the nidder by 
^elenched copper fastenings. 

The arms to the lower jntitle should be fitted to within an inch 
' of the full^breadth of the nidder, which prevents the latterfrom 
splitting. 

The shape of the rudder should give a pleasing appearance, 
and the full width carried down to the upper edge of tJie keel. 

I The upper ancl lower braces are secured to the stempost by 
denched rivets, not simply by a French nail clenched over a 
Toove fitt«d in the countersunk hole. The securities of tlie pintle 



I' 

t 
p 

■ 

C 

: 



SHIPS' BOATS 




I 



Fiu. loo.- — Kudiii^r iilliH-liril I uii|iiiiin-atini dinghy 



arms to *he ruddw are 1 
also of lieavy copper 
nails and well clenched. 
Oudgeons, which 
are driven iat*i the 
atempoat, depending 
for their security on 
a rough or jagped 
edge, should never be 
allowed ; and in sqiiarc- 
Btemed boats, where 
the upper security must 
be attached to the 
transom, the spijjot of 
the gudgeon should be 
long enough to paaa 
through the-etempost 
and be clenched over 
a washer on the face 
of tlie latter or secured ] 
with nut and screw. 

TUe common prac- ] 
tice is to fit rudders ] 
with pintles and braces | 
as de-acribed, but this 
arrangement is con- 
sidered to be an infe- 
rior one, and makes the 
operation of shipping 
a heavy rudder one of 
f;reat difficulty and | 
danger. 

The best method is ] 
by fitting a guide bat 1 
on the sternpost, andl 
with a claw type ofi 
jiiTitlo well secured to'l 
till' rudJer, the details! 
of which are shown inj 
Fig. 101. Allgood-cla 
pulling boats and mo- 
tor boats are Ettedwithl 
rudders of this design. 




— ELEVATION — 



C//£-£/C P/£rC£ 



^ mmm^^ 



f^oDoea 




2^ 



t 




~ PLAN AT UPPER ARM - 



S/fAC£ 



LOW£^ A/fAf 




" PLAN AT LOWER ARM - 
Fio. 101. — Details of rudder hinged on guide rod. 




— ELEVATION AT HEEL — 
Jl'io. iOa.^Dut.iilii u£ ruddLT. AlU-mutivi; method of hinjpug. 



CONSTKUCTiON OF CLASS U OPEN LIFEBOATS 183 

Where rudders are of siic^h a size and weight as to make them 
somewhat difficult to ship, an cxcollent practice exists among 
some boatliuildcrs of con8tructiii<; the rudder an illustrated in 
Fig. HI2, The iron rod, in this caac, ia attaclied to the rudder, 
and not to the aterniwat, by well-secured amis. At the head o£ 
the sternpost.ia a hinf^od socket, into which ia sliipped the iron 
rod of the rudder, when the latter is in the horizontal position. 
The rudder ia then attached to the boat. The socket is hinged 
over into a vertical position, which allows the rod to slide into a 
grooved guide bar attached to the etenipoat. Tlie head of the 
rudder is arranged to take a tiller in addition tai a yoke and tines. 

Yoke huM arc unsuitable when iwiliug a boat, and the general 
practice is to ht a tiller. Both the rudder and tiller must be 
secured to the boat by lanyards, eyebolts being fastened to the 
gangboard for the purpose. 

When a heavy sea ia running it becomes a difficult operation 
to control a boat with a rudder. With this in view, all boata 
must carry a steerinij oar. 

The simplest, most efficient, and yet one of the oldest methods 
of holding the steering oar, ia by fitting a wire ffrommct, served 
over with marlin stuff or spun yarn. This is seized behind the 
ring bolt and a good security made. The length of the grommet 
should be such that the blade of the eteerin^ oar can easily L 
inserted and the oar iised on cither side of the sternpost. 

To protect the capping of the gunwale, rubbing pieces are 
fitted on each aide of the atcrupost for about 15 in. in length, a 
secured to the gunwale by screws. The thickness ia about 
I in., and the upper surface well roiuided into the sternpost knees. 
It is much easier to repair a rubbing piece, than a gunwale which 
has become damaged through the continual use and chating of 
the steering oar, An illustration of the arrangement is shown ii 
Fig. 103. 

In a " square stern " boat a rowlock is usually cut in the 
transom for the purpose of sculUng, The steering grommet, in 
this case, is seized behind the ring bolt in the usual manner, and 
with the rowlock combined, provides an efficient arrangement 
for working the steering oar. 

Several other methods are in operation for taking the steering 
oar, by fitting suitable crutches, as shown in Figs. 104 and 105. 
The most expensive, but the most reliable, is the method illus- 
trated m Fig. lOj. A chock is fitted on each (juarter, about 18 in. 
from tho sternpost, an<l bolted through the sheer strake and 
gunwale, through which is pierced the hole to take tho crutch. 



SHIPS' BOATS 



In the rnitch i)Iat« and fiunwale a keyway is cut to allow the 
fciithor piece, attached to the shank of the crutch, to enter in a 




fore-and-aft ilircction. WJien the crutch is turned round to its 
correct [Hwitioii for tukiiijr tlic steeriDjj; oar, the key, or feather 
piwe, comes into contact with the lower edge of the gunwale 
and prevoiits the cnitch from lifting. The heel of the crutch 
should also be swinetl by a chain lanyard to the boat. 




Wien tiic steei'inj; oar in inserted in tlie crutch, the hiti;;ed top 
ia sei'iired in i)o8ition by a yiu attaclied to a chain. The height 



I CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 185 

I of the cnitcb is an-anj^ed to allow the steering oar to oleai the 
^ 8t«rnpoat head. 

In any case, tlie cratches should be luade portable, otherwise 
I they become a source of danger to the boat in fouling ropea and 
1 wreckage. 

Stem and 5k^ Bands. — The heads of stem and sternpnst must 

I be shaped so as to facilitate clearance should the boat be fouled 

* by a rope or wreckafje, and they are trimmed so as not to projett 

above the gunwale more than ia necessary. Some firms cut them 

flush with the gimwale. The practice saves a little labour, but 

spoils the appearance of the boat and leaves too sharp a 

projection on the stem. The stem band is made of wrought 

iron, and extends from the apron, over the stem head, to about 

2 ft. abaft the stem and keel scarph. It is fitted to the actual 

width of the stem bearding and follows the run of the fullness 

, down to the heel of the stom, so that the band becomes of some 

I real value to prote'^t and strengthen the keel and stem scarph. 

The practice of fitting cope iron to serve the purpose of a 
V stem band is of little value for strength or ornamentntion. 

Recently an alternative arrangement has been allowed whereby 

■ convex iron may be used, provided the breadth is not less than 

two-thirds the full siding of the stem ; a very ugly stem will be 

the result, and few boatbuJlders of repute will work to such a 

method. 

The ske^ hand extends from the lower rudder brace to two feet 
I forward of the keel and stempost scarph, 

A standard mould or thin batten should be supplied to the 
smith, giving the correct shape of atom band required, and 
indicating thereon the correct praition of the securities, so as 
to avoid the fastenings of stom or ske^ bands fouling those 
. securing the stem and stenipost to the deadwoods and aprons. 
Figs. 43 and 44 show the bands fitted in position. 
LUe or Grab Lines. — Where upper hand-rails are fitted at the 
^ gunwale, the life-lines are secured through the rail as shown in 
Fig. 94 A. 

The usual practice is to supply the rings attached to staples, 
which are secured through the planking and timbers just beneath 
the rubbers, and clenched over washers fitted on the inside face 
of every fourth timber. Tapered wedges of larch or other suitable 
, wood are fitted between the timbers and planking, in way of the 
staple, to provide a proper hearing for the planks on the timber 
and prevent the former from splitting when clenching up the 
staples. This arrangement is shown in Fig. 94 d. 



186 .SHIPS' BOATS 

An alternative metlKKl of securing tlic r 
profen-ed, is by the iiye of nuts and screws ii 



I, and on^ 
ieu "( Btaples, the 




nuts being hove up on washers having the points of the 
slif^htly ulenched over the nut. 

The life-lines are bccketed around the outside of the 



/> 




CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 187 

through the rings, with full loops of suflficient length to reach 
within a short distance of the water-line. Allowance should, 
therefore, be made for the sheer of the boat to enable the bottom 
of the loops to remain parallel to the water-line. 

The photograph of a completed 28-ft. lifeboat, Class Ia, in 
Fig. 106, shows the life-lines secured in position. Incidentally, 
this picture also shows the relative size of a boat, in comparison 
with that of a person. The gentleman standing at the stem of the 
boat is Mr. Thomas Stout, the Head Foreman of .the Caitsburn 
Boat Building Co., Greenock, who has done much by his personal 
initiatiYe and attention to details, to raise the standard of 
workmanship in that particular district. 

The quality of the hues should be considered : 2 in. Italian 
hemp is very suitable for the purpose, and is least affected by 
the weather. The common hemp rope sometimes placed on 
boats to serve as life-lines, becomes of little use after six months 
of service, as it quickly shrinks, becomes taut between the rings 
and out of the reach of persons struggling in the water. 

Ordinary eyes screwed into the rubber are very objectionable, 
for after exposure to the salt water they easily break off. 

The natural thing for seamen to do when launching a boat 
outboard from ordinary radial davits is to lay hold of the life- 
lines for leverage ; hence, the necessity for some substantial 
security. 

It i^ an advantage to fit a seinefloat in each bight of the hemp 
rope to prevent the latter from twisting, as this provides a 
better security or hand grip for the pei-son holding the life-line. 

Equipment Lockers. — All Hfeboats which are fully equipped, 
including the " square stern " boats of Class III., if they form part 
of the statutory equipment of a vessel, should be fitted with at 
least one locker to accommodate some of the details of equipment, 
protect them from the weather, and give the maximum amount 
of space in the boat for seating the total number of persons. 

The usual practice is to fit a locker at each end of the boat. 
Some shipowners make the additional provision of having lockers 
fitted under the thwarts. 

Portable bottom boards are placed in the end lockers above 
the keelson to enable the equipment and blankets to be kept dry. 
Hinged doors are fitted with slip bolts. Portable doors are not 
recommended, because of their liability to be lost overboard, but 
where the mast is stepped at the foremost thwart, they can 
hardly be avoided. 

The statutory rules, at present, do not insist on the provision 




- PLAN - 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 189 



of these lockers, and it is left to the common sense of the individual 
to see that they are fitted, for the necessity is obvious to every 
ship's officer. 

The arrangements are shown in Fig. 108. 

Mast Step. — ^The method of securing the mast step is one of 
importance. Instances have occurred, resulting in loss of life. 



ST£P 



T7T 






:i 



4 



KIEL50H 



S = r..rr 



:' 





f<£EL SO/V V¥/TH CHe£n 




SECTION 



\A EVATION 
Fig. 109. — Wooden mast step. 



through the mast and sails going overboard owing to the fitting 
of an inefficient step. 

In the first place, the thwart taking the mast hasp should be 
increased in width, and the arms of the hasp well secured to the 
thwart by bolts. Screws are considered to give insufficient grip 
for the purpose. Details of mast hasps are given in Part VI T., 
Section B. 

The keelson must not be cut to receive the heel of the mast, 
the step is therefore fitted on top of the keelson and secured 



fffor^ S7CR 





SECTION 



ELEVATION 
Fia. 110. — Iron mast sU^j). 



thereto with good stout screws and supported with cheek pieces 
covering the full depth of keelson and thickness of step, the com- 
bination being secured with nut and screw bolts as shown in 
Fig. 109. 

. Unless the keelson is checked over the timbers, it is an 
advantage to fit filling pieces between the timbers, planking, and 
keelson, in way of the mast step. The securing bolts through 



190 



SHIPS' BOATS 



the koclson and keel are arranged to give support to the step, 
and so make the connections as rigid as possible. The st«p and 
che(*k pieces are made from English elm. 

An iron .sfrp is sometimes fitted as illu8trat<xl in Fig. 110, the 
clieek j)ie('es would l)e an additional advantage and relieve the 
stress on the screws. 

Foot Spars or Stretchers. — These must be of sufficient size 
and strentith. They are placed in the most suitable positions for 
tlio cflicicMit use of the oarsmen. In the largest types of pulling 
boats, lower cross seats are fitted to provide the full seating 



rooTSP^i^ 







TA/^K CAeA 0//VC I 




ClifAT ^ 



\ 



\ 







Fk;. III. 

A, stretcher rl-at litteil to Mlgc strinuer. 
r». ,. ,, tank I leading. 

('. iMctlioil of littlii,? btretchers. 

acccuninodntion and ar(» also utilised to serve the purpose of 
stiotclicrs. 

\\ hci<» cross-srats are not littcd in a boat supplied with 
buovaiicv air-casos. tlir stretchers are usually made of stout 
pieces of Aincricaii ohn, about 2 in. square in section, fitted into 
cleats attached to tlie tank cleadinu bv screws from the back, as 
illustrated in Fi;js. Ill u and c. 

In open l)oats of Class III. the cleats are litted to the bilge 
strin,i:<*r, which is of sutlicicnt liei^ht to allow the footspar to 
clear the keelson. They are fastened to the stringer before the 
latter is secured in jiosition. 

Alternative positions are made for the stretchers, to suit the 
convenience of the rowers. (See Fig. Ill a.) 

Towing Bollards.— -On a passenger vessel where a large number 



■construction of class Ia open lifeboats 191 

o£ lifeboats are carriwl, including one or more motor bnata, the 
latter serve a very useful purpose in keeping the pulling' boat* 
fj^ljether should the necessity arise. Provision should therefore 
be made in all the boats to fit towing bollanls, to enable the motor 
l)uat« Ui conne<'t up with the pulling boats and relieve the oarsmen. 

TKe use of the ring bolt in the stem for this purpose should 
be avoided, as experience proves this practice to be one accom- 
panied with grave risk to the occupants of the boat. The 
Admiralty insist on the fitting of towing liollards in all cutters 
and whalers, to enable large numbers of men to be safely carried 
and the boats towed behind a motor or tug-boat. 

A suitable method of fitting this bollard ia illustrated in 
Fig. 108. It consists of a portable strongback, made from 
Danzig or English oak, which fits into clamps secured to the 
gunwale. These clamps may be of wrought iron, but a neater 
job is given by a metal castii^, owing to the difficidty of securing 
the two bevels at the gunwale. The starboard clamp is arranged 
to hinge to permit of the insertion of a strongback. Attached to 
the centre of the strongback is a wrought-iron hasp, or clamp, 
which supports the bollard. The latt€r is made from EngUsh 
ash, with a square section having its edges roimded to accommo- 
date the tow-rope. 

The heel of the bollard is circular, and secured in position by 
piercing the gangboard. The bollard cannot jump or lift pro- 
vided a drop uose-pin is fitted beneath tho gangboard passing 
through the heel of the bollard, and having its upper surface 
flattened to prevent any movement. The pin is secured to the 
boat by a chain lanyard. 

Plugs. — Each lifeboat is fitted with two plugs for each plug- 
hole. The position must be one of easy access, and the bottom 
boards arranged accordingly. Tho box to take the biimacle 
compass is place<l imder the thwart immediately on the fore side 
of the stem-sheets, to allow the ateeraman a clear view of the 
compass. This box should be arranged to be well clear of 
tbe plugs. 

The common practice is to fit a cork plug into a brass socket, 
as shown in Fig. 112 a. This litting cannot be recommended, 
as the writer has repeatedly found it to leak, particularly at 
the metal spindle passing through the cork plug. The material 
in Uie srxiket is paired down to such an extent as to make the 
arrangement of little value. To serve its purpose, a plug must bo 
of substantial scantling and should make a watertight connection 
with the socket. 



192 



SHIPS' BOATS 



Fig. 112 B shows an automatic plug sometimes fitted to steel 
boats. 



METAL SOCKET 




— SECTION- 




rsgT 




HAMMenrL} ovfff 



- SELCTIOM 



^-. SOCKET ,. 

"2) . - ^. -2) 




c 



- PLAN - 







SNELL plating 



B 



^t' *•.. COVtfp RAISED 
V-* ^CLJP LATCH 



CLIP-*- 




THUMB 

LCAre 



Li^rffeff^ K COVER 



"•^ — wr^'i"' 




-SeCTION- 

HiNce 




CuiP 



-PLAN- 



Fio. 112. — IXtailH of plugs. 



Fig. 112 c is a very useful and substantial type of plug. It cannot 
be detached from the socket, and by unscrewing; it allows the 



CONSTRUCTION OF CLASS Ia OPEN LIFEBOATS 193 

water to drain from a hole in Uie side of the spigot. A leather 
washer makes a watertight connection. 

Fig. 112 D is an excellent fitting, placed on the market by 
Ellisons (Liverpool), Limited, and named the " Agrippa " Patent 
Boat Plug. It consists of a screwed socket, attached to which 
is a hinged cover faced with leather. The cover is brought to 
bear on the seating of the socket with the aid of thumb cleats 
on a clip hatch, and wedged in position by the latter catching the 
clip^. attached to the socket. 

Ordinary soft pine plugs are sometimes fitted, attached to the 
boat by strong lanyards. 

It is good practice to secure a pad piece on the outside surface 
of the planking in way of the plug hole, particularly when soft pine 
plugs are used. The thickness of the planking is considered to 
be insufficient to take the sockets or to provide ample material 
for the securities without being pierced. 

Bottom Boards, Stern and Head Sheets. — To protect the 
timbers and fastenings of plank landinjrs, bottom boards are fitted 
and made readily portable. Care should be exercised to ascertain 
that they clear the biscuit tanks, because it is usual to fit the 
latter after the bottom boards are in position. 

The bottom boards come in for a good deal of rough usage 
and should be made from fairly tough material, such as teak, 
elm, or larch, not less than | in. in thickness and well secured 
together. 

The stern and head sheets are the platforms situated forward 
and aft at the ends of the boat, and are iLsually made portable. 
The common practice is to make them from ordinary flooring, but 
good-class boatbuilders fit portable gratings, which finish off the 
appearance of the boat without increasing tJie cost to any 
extent. 

Pad Pieces in way of Stowage Chocks. — To protect the plank 
landings from the effects of launching and housing the lifeboats in 
their supporting chocks on deck, pad pieces should be fitted, for 
about 15 in. in length, to the outside surface of the planking in way 
of the chocks. In order to maintain a flush appearance, in a 
clinker-built boat, tapered pieces are fitted in a similar manner 
to an inside doubling, and secured to the timbers. 

The fitting of the supporting chocks to the form of the boats 
now becomes an easy procedure, and as the standard positions 
for these are situated at a quarter the length of the boat from 
the ends, the boat])uilder can secure these pad pieces before the 
boat leaves the vard. 

O 



194 SHIPS' BOATS 

Inspection during Construction. — ^All boats which form a part 
of the statutory equipment of a vessel, must be constructed under 
the supervision of a ship surveyor from the Marine Department 
of the Board of Trade. 

The Admiralty have a special staff to undertake the oversight 
of all types of pulling and motor boats, building for the Naval 
Service. The Overseers devote their whole time to this particular 
work ; they have a very detailed specification to follow, and know 
exactly what they want. The supervision and the construction 
therefore proceed along satisfactory lines. 

The inspection must be carried out systematically, and the 
visits arranged to prevent any delay to the construction. This 
can only be done by the appointment of inspectors who have had 
some experience in the profession and are permitted to devote a 
reasonable amount of time for the necessary supervision. 

There should be at least four separate visits for inspecting 
particular portions of the boat during construction, which are 
as follows : — 

1 . Wlien the frame is complete, i.e. the keel, stem, stempost, 
aprons, deadwoods, and hog-piece, have been trimmed, secured, 
and ready for painting or varnishing. An identification number 
is then cut in the keel, wliich follows the boat throughout its life 
on board anv vessel. 

The quality of the material, particularly the crooks, together 
with the fastenings, can thus be examined before the planking is 
commonced or any i)aint applied. 

2. Inspection of planking before timbering. To enable a 
good soaking coat of whito-load paint to be worked on the inside 
surface of the planking, and thus allow the material behind tlie 
timbers to bo painted, it is necessary to inspect the planking 
immediatoly before the timbers are bent into position. Oppor- 
tunity is taken to reject any defective planks, particular attention 
being paid to the efFicioncy of the soleing, the snapeing away 
at the hood-ends and the faying surface of the apron. Where 
doublings are required they should be fitted and fastened before 
timbering. 

3. Inspection of internal fittings, final inspection of planking 
and fastenings before painting. It is necessary to carefully 
examine all securities at the rising, stringers, thwart knees, 
thwart ends, mast hasp, mast step, gangboard, lifting-hooks, etc., 
and watch for butted timbers at the hog-piece. Inspect the 
])uoyancy air-cases, mea.sure their capacity, and test them by 
immersing in a tank of water. Measure tlie length, breadth. 



CONSTRUCTION OF CLASS Is OPEN LIFEBOATS 195 

and depth of the boat ; ascertain the capacity by Stirling's Rule 
if required. 

4. Final inspection before delivery. It is necessary to open out 
the portable floors in lockers, stem and head-sheets, to ascertain 
that all shavings have been cleared out of the boat. Make sure 
that the lifting-hook securities are satisfactory. Inspect the 
various hull fittings. Ship the rudder and ascertain if there is 
ample clearance. Try the steering oar in the grommet. Make sure 
there is suflficient seating accommodation for the total number of 
persons allocated to the boat. Step the mast, spread the sails, 
watch the traveller to see if there is ample clearance. Try the 
sheet ropes for length. Secure the shrouds. Examine details 
of equipment. See that the approved items of equipment are 
secured to the boat with lanyards. Carefully inspect the plugs. 
Secure the water breakers with lashings. Look at the life-lines 
and try all crutches in place. Cut dimensions on the correct side 
of the stem, and stamp the date of final inspe(^;tion and initials 
of the Surveyor. 

A few saUent features to remember — 

Secure the interest and company of the foreman at every visit 
to the yard. 

Be straight and definite in all your demands. 

Mark defects on the boat, and give your requirements in 
writing before leaving the yard. 

Don't keep anyone waiting. 

Don't ventilate your knowledge. You are " summed up " 
after ten minutes' conversation with a practical boatbuilder. 

Be of some assistance, don't keep all the information stowed 
away in portfolios at the office. 

The details associated with Ufting-hooks, sails, equipment, 
etc., are dealt with in their own particular section. 



SECTION B.--CONSTRUCTION OF CLASS Ib OPEN 

LIFEBOATS 

The midship section of a Class Ib open lifeboat is shown in 

The construction is identically the same as that of a lifeboat 
of Class Ia, with the exception that external buoyancy is fitted 
in addition to the watertight air-cases, and with a slight reduction 
in capacity of the internal buoyancy. 



196 SHIPS' BOATS 

The total volume of the watertight air-cases in the Class Ia 
lifeboat must be at least equal to one-tenth of the cubic capacity 
of the boat, and in the case of the Class Ib lifeboat, the volume of 
internal buoyancy given by the air-cases must be at least equal to 
7| per cent, of the cubic capacity of the boat. 

When a lifeboat of this class is constructed of metaJ, an 
addition should be made to the cubic capacity of the airtight 
compartments (internal buoyancy), so as to give it buoyancy 
equal to that of the wooden boat. 

If the exterfial buoyanaj is made up from cork, its volume, for a 
wooden boat, should be not less than thirty-three thousandths 
of the cubic capacity of the boat ; if of any material other 
than cork, its volume and distribution should be such that 
the buoyancy and stability of the boat are not less than that 
of a similar boat provided with external buoyancy of cork. 

If the internal caj)acity of a Class Ib lifeboat is 500 cub. ft. 
the capacity of the internal buoyancy tanks will be — 

7 J% of 5(X) = 7-5 X 5 = 37-5 cub. ft. 

and the volume of cork external buoyancy — 

500 X - ^ =16-5 cub. ft. 
1000 

This gives a total volume of 54 cub. ft., being an addition of 
4 cub. ft. to the 50 (jub. ft. of watertight air-cases required 
for a Class I a lifeboat of the .same dimensions. 

Fig. 113 shows in detail how tliis outside buoyancy is made up 
and secured to the structure of the boat. 

The same principle of constniction is applicable to the 
Class II A open lifeboats. 

The use of ruslies, cork sliavings, loose granulated cork, or 
any other loose graimlated substance, and the use of apparatus 
dependent upon inflation l)y air, are not permitted for the purpose 
of external buoyancy. 

The quality of the cork must be of the very best and obtained 
in long continuous slabs, well piimed together and to a wooden 
backboard not less than \ in. in thickness. 

Its form in section should be such that it will not be liable to 
be torn away by contact with ilie ship's side when the boat is being 
lowered, and its sliape maintained by means of wood sectional 
diaphragms secured to the backboard. 

The operation of pinning and securing the cork must be 



CONSTRUCTION OF CLASS Ib OPEN LIFEBOATS 197 



efficiently done, otherwise- the external buoyancy becomes of 
veiy little use after the boat is in service. 




£DG£S W£iL 
ROUr/D£D 




MCTAL P/yV 



WOOD OlAPHffACM 

secTfofvs ^frreo ro 







'/tST ££L€)^ 



BAND 
^ MtrALPfN 



BJtrre/tfS ABOUT 2^'ki/^ 

oveff f^oores o^r/AraejfS 



- PART ELEVATION - 



- SECTION- 



- Elevation - 





SL/rCA f*f£C£'(¥f6o. 



coAA r/rreo /^3L£Afcr^s ST/7Ars A^erf^cse tma/^ p. 



^ ^^^^W^^ 



d..^.l. 



Fio. 113. — Mctiiod of fitting outside buoyancy to lifeboats of Classes Ib and 11a. 

The cork, backboard, etc., are then covered with a good quality 
waterproof canvas and well painted. 

The cork sections are made in tbree lengths, on each side of the 
boat, and secured to the planking in such a position that its lower 



19^ SHIPS' BOATS 

edge amidrihipa is a few inches above the kwd wmter-hne of the 
boat. They are made portable bv fitting apper and lower stnp6 
of wood to act aa a bearing for securing thereto the external 
buoyancy. These battens are about 2J' x IJ' and secured to 
the timbers by clenched fastenings ; they usually take the run 
of the plank landings. 

Galvanised iron straps about 3' X i^ with strong hinges 
at the top and IxAUmi, and spaced not more than 2 ft, 6 in. are 
arranged to support the several lengths of cork combination. 
In way of the butts the breadth of the straps is slightly increased 
to provide sufficient bearing for the two ends. The edges ot 
the iron straps are well rounded to prevent damage to the canvas 
and cork. 

Tlie upper and lower battens provide an air space between 
the plankiri;: and the external buoyancy. The hinges attached 
Uj the straps are secured to the battens by three screws care 
being exercised that they do not pierce the planking. The pins 
in the liin^^'es should be made of metal. 

The two end lengths are slightly tapered ; and to prevent 
damage t<; tlie cork when bringing the boat alongside a jetty or 
accommodation ladder, wooden sliver pieces are secured to the 
planking', as shown in Fig. 132. 

The usual procedure is for the boatbuilder to fit the battens 
and secure them in position, make the backboard to suit, prepare 
tlie diaplira<(m sections and secure them to the backboard. Wood 
He( tioim are forwarded to tlie smith to enable him to prepare the 
iron strups and hmges. The backboard, etc., is then given to 
the sailinaker or a maker of life-jackets, who prepares the cork 
slabs, secures iliem to the backboard, and covers the whole with 
tlni ai)prov(Hl type of canvas. 

Tlie (|uality of Uui cork, etc., should be inspected before it is 
covered witli llie cuiivaH. 

Ill eases where the stability of boats has been found to be 
delicient, and in order to increase the moment of inertia of the 
watiu* plane, ilw iittin«: of cork outside buoyancy has often been 
resorted to. 

It is inii^ortant to remember in arranging the overhang of the 
davit.s that account must be taken of the additional breadth 
LMven bv the outside buovancv attached to a Class Is lifeboat. 
The rtH'o.auised breadth of the boat is the greatest breadth to 
outside of planking, and not to the outside of ext<jrnal buoyancy. 
The diam(*ter of davitvS carrying this type of boat is, therefore, 
larger than a davit under which is stoweil a lifeboat of Class Ia, 



CONSTRUCTION OF CLASS III. BOATS 199 

on account of the greater outreach necessitated by the fitting of 
external buoyancy. 



SECTION C— CONSTRUCTION OF CLASS III. BOATS 

The piidship section of a Class III. boat is illustrated in Fig. 7. 
This type of boat is constructed in a similar way to an open 
lifeboat of Class Ia, with this exception, that buoyancy air-cases 
are not fitted. 

The construction is practically confined to the " clinker " 
method. They very rarely exceed 22 ft. in length ; in reaUty they 
are Ught pulling boats, and it is quite probable they are used 
with greater frequency than the larger lifeboats carried on 
board a cargo vessel. 

Passenger vessels are not permitted to carry boats of Class III. 

In a foreign-going steamship, not certified to carry more than 
twelve passengers, and certain other vessels mentioned in 
Section A, Part 11. , a proportion of the total number of boats to be 
carried may be of Class III. As an example, in the case of the 
foreign-going steamship referred to, if the total number of lifeboats 
required by the Life-saving AppUances Rules exceeds two, a boat 
of Class III. may be carried in lieu of one of them, and if the 
number exceeds three, one or two boats of Class III. may be 
carried in Ueu of the same number of lifeboats. The Class III. 
boats as well as the Class I. lifeboats, should be attached to davits. 

It is important to remember that when a vessel is certified to 
carry a number of passengers, not exceeding twelve, and which, 
if it were not certified to carry passengers, would be subject 
to rules governing foreign-going steamships not certified to carry 
passengers, or a steamship trading within home trade limits, but 
not certified to carry passengers, as the case may be, it is subject 
to the rules governing the boats for the latter classes, and not to 
those in any other class. Under these conditions a certain 
number of Class III. boats may be carried, but steamships certified 
to carry more than twelve passengers, must have buoyancy air-cases 
fitted to the whole of the open lifeboats carried on board. 

Every boat which is carried on board a vessel is classified, 
provided that it forms a part of the statutory equipment of the 
vessel. Boats which are carried in addition to the equipment, 
such as working boats or the captain's dinghy, need not be 
classified. 

Class III. boats must, therefore, be built under inspection, 



200 SHIPS' BOATS 

and conform to all the regulations issued by the Board of Trade 
as to scantlings and details of construction. 

In the case of defective planking or damage, a Class I. lifeboat 
possesses the buoyancy air-cases as a secondary means of keeping 
her afloat, but the Class III. boats depend entirely upon the 
quality of material and workmanship for maintaining herself in a 
seaworthy condition. Hence, the importance of careful scrutiny 
during the progress of construction. 

Some builders are inclined to look upon these boats as being 
of less importance than the lifeboats, but, strictly speaking, they 
should be constructed with even greater care than the larger 
boats. 

There are bound to be anomalies in all rules, but many people 
cannot understand why it shoidd be necessary in the case of a 
small sailing vessel, say a ketch of 40 tons gross tonnage, 
and running between Glasgow and Ayr, carrying an open boat 
of Class III. sufficient to accommodate all persons on board, 
should, immediately a small motor is inserted as an auxiliary 
means of propulsion, be required by the Life-saving Appliances 
Rules to carry a lifeboat of Class 1., i.e. buoyancy air-cases must 
be fitted to the Class III. boat. 

The installation of a motor has converted the sailing vessel 
into a steamer and brought her under a new classification of the 
L.S.A. Rules, but tlie necessity does not appear clear. 

It is important to remember that all Class III. boats must be 
equipped in every detail the same as the Class Ia lifeboats 
carried on board. 

Ill IG-ft. boats and below, it is not usual t(; fit side seats extend- 
ing over the wliole of the tliwurts as in a lifeboat of Class I. of 
similar dimen.sir)ns. The amount of equipment which must be 
(•allied in accMjrdaiicc with the reirulations is sufficient to limit 
tlie number of persons whicli can be reasonably assigned to the 
boat. Very few boats of Class III. are constructed "double 
bowed/' they usually have S(|uare sterns which allow greater 
accoiiimodatioii on the stern benclies. In boats of 18 ft. in length 
and upwards it becomes necessary to extend the seats in order to 
provide sufficient area for seatin<:;. 

SECTION D.— CONSTRUCTION OF CLASS IIa OPEN 
LIFEBOATS WITH COLLAPSIBLE BULWARKS 

A GENKRAL description of the diilerences between the various 
types or clashes of boats, has already been given in Section B of 



I 



^^ thici 
^H tiiicl 



CONSTRUCTION OF CLASS IIa OPEN LIFEBOATS 201 

Part n., aud the purpose of grouping; tlie various aectiona under 
Pait IV. is to ptuvide discussiou, in fuller detail, of the mcthoda 
of constructioQ iu each individual class of boat, 

Fi(;. 4 gives, in outline, the niidahip section of a Class IIa 
open lifeboat, and it will be seen that it differs in form from 
the ordinaiy type of open lifeboat (Class L), having a much lower 
freeboard to the top of the solid hidl. Additional protection ia 
obtained by the fitting of collapsible bulwarks. 

Comparing boats of the same length but differing in claaa 
we find that the freeboard of a 28-ft. lifeboat of Class Ia is about 
24 in., and that of a 28-ft. lifeboat of Class IIa is 9 in. measured 
to the solid hull, but with the bulwarks fixed in position, is 
increased to about 33 in. 

The provision of collapsible bulwarks allows this type of boat 
to be stowed under open lifeboats of Class I., which are attached 
to davits, or they may be stowed inboard one above the other 
or singly, provided trauaporting arrangements are fitted under 
the boats to bring them under the davits with rapidity, for 
launching overboard. 

This class of boat appears to find most favour with ship- 
owners who require to be supplied with a number of lifeboats 
having collapsible bulwarks. 

The lengths of the boats vary from 24 to 3U ft., the breadths 
from 8 to 9 ft., and the depth without bulwarks is about 2 ft. 

Watertight metal air-cases are fitted at the sides in a similar 
fashion to Class I. boats, in order to provide the necessary reserve 
of buoyancy. 

The general structure of the hull is made up of two thick- 
nesses of woikI planking, worked in a fore-and-aft directi<m, and 
flo arranged that the seams of the two thicknesses break joint 
one with the other. An approved fabric is worked between the 
two thicluiesses of plonking. 

For vessels whose trade continually takejs them through the 
tropics, it is very essential that the planking should be of material 
that is least affected by the extremes of teniperature. Two 
thicknesses of Honduras or Lagos mahogany make an excellent 
hull, and it is the opinion of many, that woi>d of inferior quality 
to mahogany should not be permitted in these classes of boats, 
as they are not used or inspected with the same frequency as 
Class I. boats ot the open type. In cases where passenger vessels 
itantly employed in a temperate climate, the double 
thickness of wood planking is sometimes made up of an inner 
tluckneas of larch and an outer thickness of yellow pine. 



202 SHIPS' BOATS 

The boat is double bowed, having a " deck " at the ends and 
over the buoyancy tanks at sides, with a central open well the 
full depth of the hull. The deck, or covering, over lie buoyancy 
tanks forms the upper surface of the hull bom which the free- 
board is measured. Above the '^ deck " are fitted the collapsible 
bulwarks, which, hinge down in their stowing position. 

The standard type of Class IIa lifeboat at one time consisted 
of the hull as described, with solid wooden bulwarks fitted for a 
little more than half the length of the boat amidships, in way of 
the straight sides. Between the wooden bulwark and the ends of 
the boat rotproof and waterproof canvas was fitted. The bulwarks 
were kept in position by hinged stanchions, which locked them- 
selves in the upright position. Thwarts were also fitted and 
arranged to hinge down in a similar way to the bulwarks. They 
were connected together in two sections, so that the forward 
section would hinge towards the stem and the after section 
towards the stem. Locking arrangements were also provided for 
the thwarts. 

The first operation is to lift the bulwarks and then the 
thwarts ; wlien the latter are in position and persons seated 
thereon, movement cannot take place ; the upper structure is 
thus well secured. 

Outside buoyancy made up of solid cork and secured by the 
method described in Section B, is fitted on each side of the 
boat, immediately above the water-line. 

Fig. 114 shows the old standard type of Class IIa open life- 
boat, undergoing the Board of Trade rowing tests, with the 
full number of persons on board, each one being provided 
with a life-jacket. This type of life-jacket has now been con- 
demned. The particular boat illustrated was constructed by 
Messrs. Hu^^li McLean and Son, of Go van, who have had a very 
extensive experience in this and other types of lifeboats with 
collapsible bulwarks. 

The following details of construction are given for a lifeboat 
of standard size. viz. : — 

I^ongth. Breadth. Depth. 

30' U" X 9' 0" X 1' lir 

Scantlings. — These are based upon the assumption that the 
structural strength is such that the boat will be able to 
support a deadload equal to 25 per cent, greater than the 
actual service load, when supported by the slings and their 
attacliiiients. 



204 



SHIPS' BOATS 



KeBl. — Should be of oak or Americsu rock elm, 2^' X 2J', 
and free from knote and short grain. 

Stem and Sternpost. — Should be of oak, and cut from timber 
grown to shape, attaclied and secured to Uie keel by a horizontal 
scarph, as shown in Fig. 115. Nut and screw bolte are to be 
preferred for the securities, having square or oblong heads 
to prevent turning. 

Deadwood and Apron. — If a suitable crook can be obtained. 




Hie clwtilw.iinl iiiiil upiiin slioukl be in one piece, otherwise 
tlicy arc lip-scai])hed t"j;cther. They arc aided so as to 
pruticrve a good fayiug Hurfucu t'ur (lie liood-cnds of the planking. 
The seciiritic'j at the liooil-eniiH urc provided by means of one 
row of brass sercwK Jieiiru.-it llio rabbet, and a second row of 
tojipfi- roise-Leadud nail.s. 

Owiim to the lilufT I'uds and full form of boat, there is a 
[^rcat doal of initial slrcse; i>ii (ho plaiikiu^ towards the stem and 



CONSTRUCTION OF CLASS IIa OPEN LIFEBOATS 205 

stemposty which Decessitates careful treatment of the combina- 
tions at the ends, and provision must be made for fair surfaces 
to take the securities to prevent any undue stress on the planks. 
Hog*Pleee. — This is fitted in one piece the full length of the 




5 BUlHNeAO 



Fio. 115b. — C/ombinations at the ends of a ClasH IIa lifeboat. 

boat, checked under and secured to the dead woods. The thick- 
ness should not be less than \\ in., and the width so arranged as 
to give at least 1 in. each side of the keel for the landing of the gar- 
board. The hog-piece is connected to the keel by through fastenings. 



206 SHIPS' BOATS 

Bulkheads. — Owing to the particular form of this type of 
boat, having great breadth in comparison with its depth, the 
longitudinal and transverse strength is maintained by providing 
solid longitudinal and transverse bulkheads, fitted the full depth 
of hull. 

The purpose of these bulkheads is not to divide the hull into 
watertight compartments, as in pontoon boats of Classes Ic, 
11b, and He, but to stiffen up the boat for supporting the number 
of persons which can be carried. 

Drain holes are cut in the heel of all the bulkheads, and of 
suflScient size to allow water to flow freely towards the centre of 
the boat. 

When these bulkheads are fitted together they form a skeleton 
frame which dispenses with the necessity of erecting special 
moulds for the purpose of planking. 

(a) Lifting Bulkheads. — A transverse bulkhead is fitted at 
each end of the boat to take the chain slings or lifting gear. 
The scantlings are in excess of tlie other bulUieads. They are 
fitted in one piece, if possible, not less than If in. in thickness, 
of English elm or Oregon pine, preferably the former. 

These bulkheads extend the full breadth of the boat at a 
distance from the ends most suitable for the spread of davits. 
If they cannot be obtained in one piece, the separate portions 
should be well connected together with iron straps. 

(6) Longitudinal Bulwarks, — Two of these are fitted extending 
the full length of the boat, between the transverse lifting bulk- 
heads, one on each side of the middle-line at a suitable distance 
to allow sufficient space for the accommodation of the buoyancy 
tanks. They are usually made of pitch pine and scored over 
the timbers, connected to the lifting bulkheads by galvanised 
angle bars, 4" X 2Y, havin*^' at least four |-in. nut and screw bolts 
in each flan'^e. The ends of the screws are clenched over the nuts. 

The lon<^itudinal bulkheads at the sides are either extended 
beyond the transverse lifting bulkheads, to the ends of the boat, 
or a middle-line bulkhead is fitted as shown in Pigs, 115a and 
lir)B. 

(c) Transverse Wing Bulkheads, — These are usually made 
from larch, \\ in. in thickness, four in number, fitted each side 
of the boat, between the longitudinal bulkheads and planking, 
and connected to the former by galvanised iron angle bars, 
^Y X 2^", and secured by at least three J-in. nut and screw bolts 
tlirou<rh each flanjre. 

(rf) Transverse Well Bulkheads, — Two in number are fitted 



ONSTRUCTION OF CLASS IIa OPEN LIFEBOATS 207 

t the well between the longitudinal bulkheads, and connected 
9 them by angle bars of the same size as those fitted to the wing 
Ikbeads. 

(e) Diagonal Bulkhmds. — In addition to the middle-line 

_ "Jiead at the ends, two diafioual bulkheads, made from 

larch IJ in. in thickness, are fitted between the former and the 

planking. These have sometimes been dispensed with and 

extra lieavy timbers 6tt«l at the ends as compensation. 

Timbers.— Of American elm, IJ' x %", to extend from deck 
to deck in one piece and notchud into gimwale and well secured 
to the latter, the longitiidmal bulkheads, and the ling-piece, 
before procewling with the planking. 

The spacing, centre to centre, is six inches. 

Between the diagonal bulkheads and stem or sternpost, 
three solid cant ttmbera of American elm are fitt«d on each side, 
and the remaining timbers which cannot be worked in one length 
across the middle-line should be well rnnnected to the s'liwl^ 
and have their heeb checked int<j and secured to the dead-woods, 

Ganwale.— Of American rock elm, about 4° X Ij", and is 
usually fitted in two pieces in the length of boat, well scarphed 
together at one of the transverse bulkheads, sr> that tiic tatter 

•becomes a means of support to the scarph. The scarpbs are 
shifted clear of the same bulkhead. 
Galvanised wrought-imn breasthooks. with deep throats, 
are fitted at the aprons and ends of the gunwales, bolted with 
nuts ajifl screws, the nuts being on the iron breasthooks. 

Covering-Board,— A covering-board of oak or American 
elm, 1 in, in thickness, is fitted above the gimwale, as shown in 
Figs. 11.") and 116. This forms a protecting strip to the deck 
ends or hatch covers over the buoyancy tanks. 

Web Beams and Lower Thwarts,— About four in number 
lower thwarts are fitted between the end transverse bulkheads, 
for the full breadth of tlie boat from gunwale U} gimwale. Thev 
are made from pitch or red pine about 9 in, in breadth, IJ in. in 
thickness, and well secured with screws to the gunwale, longi- 
tudintil, and transverse bulkheads. These thwarts are only used 
for the purpose of seating and not for rowing, 

Web beams, C X IJ", are fitted in diagonal fashion at the 
ends of the boat, notched into and secured to the transverse 
lifting biilkbead and gimwale. These beams stiffen up the ends 
and support tlie connections through the end combinations. 

t Short beams of oak or American elm are worked between 
nd notch«l into the gunwale and longitudinal bulkheads. 



208 SHIPS' BOATS H 

about Ij" X IJ", spaced about 9 in. apart, centre to centr^ 
These are well secured to the portable hat<:hes which cover the 
buoyancy tanks. 

Hatch Covers. — These are fitted over the buoyancy tank 
spaces and the compartments at tlie ends of the boat. The 
edges of the covering board and thwarte are rabbeted to receive 
the covers. A flush upper surface is tlius preserved fore and 
aft over the buoyancy tauks. The covers are usually made from 
pitch pine, feather and grooved, and secured to the short portable 
beams. 

To provide suitable means of inspecting the interior of the 
boat and to allow the buoyancy tanks to be removed, the hatches 
are secured to the longitudinal bulkheads, thwarts, and covering 
board, by strong brass screws fitted in cup sockets. 

The " deck " ends are permanently secured to the hull, but 
a portable hatch is fitted at each end in a similar way to the 
hatches over the buoyancy tanks, for the purpose of inspecting 
the condition of the hull. 

The thickness of the hatch covers is not less than 1 in. 

Planking, — One of the most important features in the con- 
struction of this type of boat is the efGciency of the planking. 
Sufficient reason has already been given for expressing the 
opinion that the material of the planks should be mahogany — 
either Honduras or Laj^os. Gaboon mahogany must be avoided 
as it is deficient in strength and lasting qualities. It is somewhat 
difficidt at times to discover the difference between the three 
species when they are apart. Gaboon is much lighter in colour 
and weight than any other species of mahogany. 

As soon as tlie skeleton frame of the boat is secured together, 
it is usual to turn the boat upside down to facilitate the work of 
planking. 

Two thicknesses of material are used, each about ^ of an 
inch, making a total thickness of | of an inch. The strokes are 
4 in. in breadth and worked fore and aft, the outer skin strakes 
breaking joint witli those of the inner. The inner thickness is 
completed before action is taken to commence working the outer. 
The inner thickness is secured to the timbers with wrought copper 
naib, 12 B.W.G., clenched on rooves of substantial section. 

Before the outer skin is worked, a ply of calico is laid in 
white-lead on (he surface of the inner skin. 

The outer skin nuist be carefully worked to prevent " puffing 
off " between the two thicknesses, and is secm'«l alon;,' the seanis 
to the inner skin, with copper nails, 13 B.W.G., clenched ove 




I 



CONSTRUCTION OF CLASS lU OPEN LIFEBOATS 209 

I roovea and Hpacal not tijdre than 2^ in. apart. The diameter of 
the looves is not less than g of aii iiicli. The outer and inner 
skins are secured to the timbers by copper nails, 12 B.W.G., 
clenched over looves, and also to each longitudinal and transverse 
bulkhead, with brass screws 1^ in. in length, spaced 6 in. fore 
. ftnd aft and two In each plank athwart«hip. 

The hood-ends are secured to the aprons and deadwuod, with 
' brass screws at the caulking edge and with a second inner row 
of copper nails. 

The butts are carefully arranged to secure a proper shift 
1 in the inner and outer thicknesses, and the faying suiiaces are 
T well coated with thick white-lead paint before being secured with 
I a double row of clenched copper nails. 

The edges of the garboard atrakea are secured to the hog- 
I piece. 

The number of fastenings in the planking make it very 
' necessary for the whole of the securities to be carefully prepared 
by drilling tlie holes with a bitt, and easing the planks without 
force when bending them towards the ends of the boat. 

The whole of the seams and hood-ends of the outer thickness 
are lightly caulked with cotton thread, care being exercised to 
prevent the sharp edge of the caulking tool from cutting the 
cotton fabric. 

The seams, etc., are then filled with the best white-lead putty. 

Uftfng SUng Arrangement. — The lifting bulkheads at the 

ends of the boat are fitted with forged eye-platea of the design 

i shown in Fig. 115, liavin;; V-shaped securing legs and so 

I fitted that one leg is placed at right angles to the pull of the 
aling-hook, and through bolted to the athwartship lifting bulk- 
head. The other leg of the eye plate is placed in a vertical 
direction and secured to the lifting bulkhead and to the angle bar 
which also connects with the longitudinal bulkheads, thus 
providing a fair distribution of the stresses between the principal 
combinations in the frame of the boat, when lifted by the davits. 
The arrangement of the slings is governed by the type and 
position of the davits. 

Buoyancy Air-Cases. — These are fitted along the sides between 
the longitudinal bulkheads and the planking. They are made of 
yellow metal or copper, not leiss than 18 ozs. per square foot, 
and made suitable in size to bo easily removed between the lower 

I thwarts. If over three feet in length they should be fitted with 
on internal bulkhead. The volume is 1'5 cub. ft. Jor each 
person Khich the boat ie able to accommodate, 
L 



i 



198 SfflPS' BOATS 

edge amidships is a few inches above the load water-line of the 
boat. They are made portable by fitting upper and lower strips 
of wood to act as a bearing for securing thereto the external 
buoyancy. These battens are about 2^^ X 1^^ and secured to 
the timbers by clenched fastenings ; they usually take the run 
of the plank kndings. ' - 

Galvanised iron straps about 3^ X J^ with strong hinges 
at the top and bottom, and spaced not more than 2 ft. 6 in., are 
arranged to support the several lengths of cork combination. 
In way of the butts the breadth of the straps is slightly increased 
to provide sufficient bearing for the two ends. The edges ot 
the iron straps are well rounded to prevent damage to the canvas 
and cork. 

The upper and lower battens provide an air space between 
the planking and the external buoyancy. The hinges attached 
to the straps are secured to the battens by three sclrews, care 
being exercised that they do not pierce the planking. The pins 
in the hinges should be made of metal. 

The two end lengths are slightly tapered ; and to prevent 
damage to the cork when bringing the boat alongside a jetty or 
accommodation ladder, wooden sliver pieces are secured to the 
planking, as shown in Fig. 132. 

The usual procediu*e is for the boatbuilder to fit the battens 
and secure them in position, make the backboard to suit, prepare 
the diaphragm sections and secure them to the backboard. Wood 
sections are forwarded to the smith to enable him to prepare the 
iron straps and hinges. The backboard, etc., is then given to 
the sailmaker or a maker of life-jackets, who prepares the cork 
slabs, secures them to the backboard, and covers the whole with 
the approved type of canvas. 

The quality of the cork, etc.. should be inspected before it is 
covered with the canvas. 

In cases where the stability of boats has been found to be 
deficient, and in order to increase the moment of inertia of the 
water plane, the fitting of cork outside buoyancy has often been 
resorted to. 

It is important to remember in arranging the overhang of the 
davits that accoimt must be taken of the additional breadth 
given by the outside buoyancy attached to a Class Ib lifeboat. 
The recognised breadth of the boat is the greatest breadth to 
outside of planking, and not to the outside of external buoyancy. 
The diameter of davits carrying this type of boat is, therefore, 
larger than a davit under which is stowed a lifeboat of Class Ia, 



I 
I 



CONSTKUCTION OF CLASS III. BOATS 199 

on account of the greater outreach necessitated by the fitting of 
I external buoyancy. 



SECTION C.-^ONSTIIUCTION OF CLASS HI. BOATS 

The midship section of a Class III. boat is ilhistrated in Ftg. 7. 
This type of boat is constructed in a similar way to an open 
lifeboat of Class Ia, with this exception, that buoyancy air-cases 
are not fitted. 

The construction is praoticaUy confined to the " clinker " 
method. They very rarely exceed 22 ft, in length : in reality they 
are light pulling boat«, and it is quite probable they are used 
with greater frequeuc)' than the larger lifeboats carried on 
board a cargo vessel. 

Passenger vessels are not permitted to carry boats of Class 111. 
In a foreign-going steamship, not certified to carry more than 
twelve paasei^ers, and certain other vessels mentioned in 
Section A, Part II., a proportion of the total number of boats to be 
carried may be of Class III. As an example, in the case of the 
foreign-going steamship referred to, if the total number of lifeboats 
required by the Life-saving Appliances Kules exceeds two, a boat 
of Class III. may be carried in lieu of one of them, and if the 
number exceeds three, one or two boats of Class III. may be 
carried in hen of the same number of lifeboats. The Class III. 
boats as well as the Class I. lifeboats, should be attached to davits. 
It is important to remember that when a vessel is certified to 
carry a number of passengers, not eaxeedituf twelve, and which, 
if it were not certified to carry pasBengera, would be subject 
to rules governing foreign-going steamsiiipa not certified to carry 
passengers, nr a steamship trading within home trade limits, but 
not certified to carry passengers, as the case may be, it is subject 
to the rules governing the boats for the latter cJasses, and not to 
those in any other class. Under these conditions a certain 
number of Class III. boats may be carried, but steamships certified 
to carry more than twelve passengers, must have buoyancy air-casea 
fitted to the whole of the open lifeboats carried on board. 

Every boat which is carried on board a vessel is classified, 
provided that it forms a part of the statutory equipment of the 
vessel. Boats which are carried in addition to the equipment, 
such as working boats or the captain's dinghy, need not be 
classified. 

Class III. boats must, therefore, be built under inspection, 




212 SHIPS* BOATS 

Stowing Chocks. — Three good solid stowing chocks and cover 
bearers are secured t^) eacJi of the solid bulw^arks immediately 
over th(^ wing bulkheads, so that when the bulwarks are hinged 
down into their stowhig positions, some substantial support, is 
obtained from the longitudinal and transverse bulkheads. 

These chocks are so formed that when the keel of the upper 
boat is stowed on the khigplank of the boat below, the bilges of 
th(» upper boat are resting in the chocks. 

Griping Bars. — ^Two galvimised iron griping bars, constructed 
so that the gripes are clear of the corkf ender, are supplied with 
each boat to enable the latter to be well secured in position on 
tlio deck. 

General Instructions. — The whole of the timber used in the 
construction of these boats must be of first-rate quality and well 
seasoned. All ironwork, including iron bolts and washers, are 
heavily galvanised. The boats are constructed under the 
inspection of a ship surveyor of the Board of Trade. 

Before construction is commenced, a detailed specification 
has to be submitted to, and approved by the Board of Trade, 
who also demand certain tests to be carried out, to which reference 
will be made later. 

Modifled Class IIa Open Lifeboat. — Since the issue of the 
Report from the Conmiittee on Boats and Davits, and the 
International Convention Regulations, the minds of boatbuilders 
have been stimulated, and attention devoted, to the necessity of 
providing a better protection to the occupants of the boat than 
that given by the canvas bulwarks fitted at the ends. 

The *' all wood " type of collapsible bulwark has thus been 
brought into existence by one or two well-known firms on the 
Clyde, and is consiilered to be a more reliable method of keeping 
out the water, offers a better protection to the occupants of the 
boat, and is moie serviceable and durable than the old arrange- 
ments provided in the standard t\T)e. 

The outside buoyancy has been dispensed with, and a rope 
fender litted in lieu. Two cross bulkheads have been deleted to 
allow wounded persons to be placed in the well. 

To compensate for these modifications the internal buoyancy 
provided by the watertiglit air-cfises has been increased in volume 
from 1*5 to 1"7 cub. ft. for each person accommodated in the 
boat. The minimum freel)()ard of the loaded boat is not to be less 
than that laid down in the L.S.A. Rules for the standard boat 
but increased by 15 per cent. 

A coir rope fender, not less than 4 in., made up of long 



feTRUCTION OF CLASS IIa OPEN LIFEBOATS 273 

stranda, unlaid but marled to the diameter, is fitted round the 
boat in lieu ot the external cork bunyancy. An air-space between 
the fender and the boat planking is arranged, to preserve the 
latter from the effects of rot. The general arrangemejit of this 
fender ia shown in Fig. 95. 

The hidk of boats of thia class are practically standardised 
according to the specification approved by the Board of Trade, 
but there are differences in the type and general arrangement of 
the bulwarks. 

In the interests of the various boatbuildera who have brought 



I 




out patent details in (Tinnection with this class of boat, the writer 
hsB purposely refraineil from any minute description, but illus- 
trations are given which give a general idea of the construction. 
Fig. 117 shows the patent modified Class IIa open lifeboat 
constructed by Messrs. Hugh Mcl^ean and Ron, of Govan, and the 
various details illustrated in Fig. 116 indicate hiiw the bidwarks 
are constructed and made watertight. 

The horizontal and vertical joints are made watertight by 
rubber jointing, f X |1.*, or lamp wick, the foi-mer being secured 
to the coamings by solution and |-in. brass screws 6 in. apart. 
' The bulwark ends consist of three pieces hinged together on 



314 



SHirS" BOATS 



the nutBide, so that the eD<l pieces fold over un the centre piec 
and collapse with it. 

Doors are fitted at the sides to enable peit^ms struggling i 
tliB water to he Htted over the deck in3ti?<ad of over the frunwal 
[)!' Iiulwark. 

All the vertical joints are efEciently held with wedgea i 
hawd clips. 

The whole of the arrau^emeiibs are tn'eatly in advance of tM 
tyi)e nf boat having canvas bulwarks. The bulwarks i 
the great advantage of having tapered ends for thmwing < 
the water. 

Messrs. Gouk and Nesbit, of Glasgow, have patented anotlM 
type Claas IIa lifeboat, which difTers slightly from the oq| 
previously descrjbeil, the general view of the boat, with I 
bulwarks erected in place, being piven in Fig. 118. The i 
will notice the difference in the rowing thwarts to thrwe alrei 
(lewiibcd in the general sperification, and also the ]iatent locki 
arrangements on the aides. The portable wooden end seats, w " 
slipped into position, prevent the hnlwark ends fnim eollapsiiig. ] 

The time taken to expand the boat, erect the bulwarks, aai 
place the end seats in position, was recorded as 15 8ecoads. 

The special feature of the design associated with the 
" Hercules " patent, constructed by The British Marine Motot 
and Launch (^o.^ Ltd., Whiteinch, Glasgow, is unique and orj^^ina]. 
There are the usual hinged st<?m-piecea, and folding bulwark 
in the straight- sided portion nf the boat, the latter being well- 
constructed of oak and mahogany in two thicknesses. Ui the 
tnidflhip bulwark a recess is so arranse<l to receive a slidinj; 
portion. These movable or sliding end bulwarks are niado on 
very similar lines to the principle of the " roll-top " desk, and are 
composed of vertical wooden battens of two thicknesses, with 
canvas laid in paint between, suitably bound tflgether. By the 
use of channel irons on tJie coaming and upper gunwale, which 
are raised into position when erecting the thwarts, and form a 
guide for the sliding portion to operate in, the end bulwarks arc 
pulled quickly into position. 

When tlic end bulwarks are not in use tliey are not expo3<>d to 
the weather, but slide into the recess of the strai<;ht-sided bulwark, 
and hinge down into the final stowing position witli the latt«r. 

The thwarts and seats are supported by stanchions which arc 
connected with a sliding strap, providing a mean.'* whereby the 
former are locked or imlocked simultaneously. The whole 
arrangement of the hinging; of the upper structure i« automatic in 



CONSTRUCTION OF CLASS IIa OPEN LIFEBOATS 215 



action, the simple method of raisin^^ or lowering the thwaria, 
locking or imlocking them as the case'may be. 



i 




i 



216 



SHIPS' BOATS 



Fig. 119 shows the side bulwark in position with tli^te 

raised, and having the thwarts and seate stiU in their stowing^ 
positiim. 

fig. 120 indicates the channel irons, or guide bats, in position,, 
with the seats and thwarts raised. One sliding end shutter i: 
place and the other in its stowing position within the midshipl 
bulwark, readv to be drawn out into ita connection with the steni(T 





Existing types of lifeboats of Class IIa having canvas bulwarH^ 
can be fitted with the new wooden bulwarks as previoosln 
described. A 

It is a misnomer to refer to this class of boat as a " collapsible '1 
lifeboat, for it may be confused with the Beithon type of canran 
and wood boat, which is purely a collapsible boat, and largdr 
adopted by the Admiralty where space and accommodation will 
not_allow ordinary pidling boats to be stowed. The Class Ua 
open lifeboat, and Classes lo, IIb, and lie pontoon lifeboata hav 




CONSTRUCTION OF CLASS IIa OPEN LIFEBOATS 217 

rigid and substantially built hulls, whose upper bulwarks and 
thwarts fonn the only details of the structure which collapse. 

Whatever type or special patent boat of Class IIa or pontoon 
lifeboat is carried on a passentrer vessel, it is absolutely essential 
for them to be carefully watched and periodically inspected, 
otherwise they will fail in their purpose when required in a time 
of difficulty or danger. 

There is an important feature in connection with the con- 
struction of this and other special desi^ms of lifeboats. When a 
boatbuilder commences to build a new type of boat, in addition 
to submitting a detailed specification to the Board of Trade, it is 
necessary for him to carry out an extensive series of tests before 
the design can be accepted. The writer is indebted to Mr. Hugh 
McLean for the record of tests carried out under Board of Trade 
supervision, on some boats constructed at the Govan yard. 

Surfaee Measurement. — Before dealing with these tests it will 
be well to make reference to the Life-saving Appliances Rules, 
which state that the number of persons which a lifeboat of this 
class shall be deemed fit to carry, shall be equal to the greatest 
whole number obtained by dividing the surface of the boat in 
square feet, by the standard unit of surface. 

The standard unit of surface for a Class IIa lifeboat is 3J 
sq. ft. 

The surface in square feet is determined by the following 
formula : — 

Area =• ' (2a + l'% + 4o + I'Srf + 2^) 

I denotes the length in feet from the intersection of the outside of 
the planking with the stem to tlie corre^sponding point at the 
stempost ; a, 6, c, d and e denote tlie horizontal breadths in feet 
outside the planking at the points obtained by dividing I into 
four equal parts and sub-dividing the foremost and aftermost 
parts into two equal paits {a and e being the breadths at the 
extreme sub-divisions, c at the middle point of the length, and h 
and d at the intermediate points). Keferencc should be made to 
Fig. 126. 

Freeboard — The minimum freebc^ard of boats of Class IIa 
is fixed in relation to their length. It is measured vertically to 
the top of the solid hull at the side amidships from the water-level, 
when the boat is loaded. 

The freeboard in fresh wafer shall not be less than the following 
amounts : — 



218 SfflPS* BOATS 

Length of the boat Minimum freeboard in inoHee. 

in feet. Class IIa. . Modified Class IIa. 

26 8-0 9-2 =3 9^/ 

27 8-5 9-78 = 9i^ 

28 90 10-35 = lOp 

29 9-5 10-93 = 10^^ 

30 100 11-5 =lli^ 

The freeboard of intermediate lengths is found by interpolation. 

Tests. — Before construction is commenced on lifeboat^ of this 
class the detailed specification must receive the approval of the 
Board of Trade, and certain tests must be carried out before the 
boats can be accepted and allowed on board a vessel as part of 
the statutory equipment. 

The following results of tests on a Class IIa open lifeboat were 
supplied to the writer by Messrs. Hugh McLean and Son, and will 
give the reader a good idea of the modus operatidi in carrying out 
a series of te^ts. 

The dimensions of the sample boat were : 

30 r X91'X r llJ^(l-94') 

The deck arexi was obtained in accordance with the requirements 
of the L.8.A. Rules, and the ordinates taken at the positions 
shown in Fig. 120. 

Onlinates. Multipliers. Functions. 

Stem .... 00 0-5 0*0 

a 7-2 20 14-4 

h 90 1-5 13-5 

c 91 40 36-4 

d <)0 1-5 13-5 

e 73 20 14-6 

Stonipost . . 00 0-5 0*0 

]•>"' 12 ~^-"^ 2'^'l 

231-924 sq. ft. 

Capacity of iiit(»nial buoyancy tfinks => 87*57 cub. ft. 
Volume of cxtcrual buoyancy = 11*6 „ 

Nuni])or of piMsoiLs ol)tainod from ) 232 
dock area j "^ 3-5 "^ 

Number of persons obtained from ( ^87*57 -^ 

internal hiioyaiicy j " p5 ' 

Number of persons obtained ironi)_ll*6 ^^ 
ext(»rnal buoyancy ( ~~ 0*2 ^^ 



CONSTRUCTION OF CLASS IIa OPEN XIFEBOATS 219 



STRENGTH TEST. 

The boat was attached to a spar and lifted by a crane to enable 
the stresses to operate on the hnll under service conditiona. 
Sights were fixed to the stem, sternpost, and centre thwart. 

(a) Boat light. — Sights were adjusted while the boat was on 
the quayside on level ground. The boat was then lifted by 
the crane : — 

Deflection measured =^ j-'jr in. 
Permanent set — nil. 

(b) Boat loaded with weights equal to 54 persons and equipment 
(number of persons obtained from a previous freeboard test) : — 

54 persons at 1(55 lbs. - 795 cwts. 
Equipment — 50 

Total load -: 84-5 
Deflection measured and found to be -J in. 



»» 



>» 



S/tffr 




S^SAfT 



Fia. 121. - -Strongth kst of Class IIa liff})()at. 

(c) Boat loaded. Plm 25 }H>r r^w/.— The boat was then loaded 
with weights equal to 54 persons, equipment, and an addition 
of 25 per cent, of the full load. 

54 f)ersons at 1()5 lbs. — 79-5 cwts. 

E(juipnient - 5*0 ,, 
Actual weight of boat - 38-5 ,, 

123(> ,. 
Plus 25^;,- 30-8 

15.3.8 
Less weight of boat ■— ^t^Ty 

Tost load ^- 115-0 

Deflection measured and found io be ] ;'! in. 

(d) Boai light. — All the weights wore discharged, boat landed 
on level ground, sights adjusted, and permam^nt set was found 
to be nil. (See Fig. 121.) 



>> 



»> 



>» 



5' 



220 



SHIPS' BOATS 



FREEBOARD TEST. 

(a) Boat lowered into water (partially salt) and freeboard 
examined amidships. (See Fi^'. 122.) 

Distance between water-level and top ) _^ ^ 76^ 
of Viilwark ^niwale * ) ^ 

Distance between top of " deck " and 1 _, 9' 1?^ 
top of bulwark jninwale ( 

— m 

Freeboard = 1' 5|^ 

(b) The specific ^^ravitv of water taken from the dock, at a 
temperature of (iO" F. — 1017 oz<. 

Uul(*, freeboard for 30-ft. Class IIa lifeboat = 10 in. 
Freeboard after a<ljustinent for salt water =10J in. 




Kks. 122 ¥jq. 123. 

Frc^eboard iiiid flottitiun tcsUj of Class Ha lifeboat. 

Boat while afloat was loaded with wei^^hts evenly distributed 
in order to maintain a level keel, until a freeboard of lOj in. was 
obtained at amidships. (See Fiir. 123.) Weights on board were 
then recorded as follows : — 

11)9 weiizhts at 50 lbs. each = 84*5 cwts. 
Less ecpiipment = 5*0 „ 

79-5 „ 

7i)-r) X 112 

1 g:) 



- - 54 persons. 



Tlie (leek ariNi was suHici(Mit for (Hi pers(ms. Therefore the free- 
board, in till > <'a e. is tlie ^overniniz factor which settles the number 
of persons wiiicii can ho assiirned to the boat. It will also be sieen 
tiiat the «'xt(Mnal ami internal buoyancy were sufficient for 
.58 person^. If [\w deck area had j^Mven a smaller number of 
persons tlian 51, thtMi that smaller number would have been used 



CONSTRUCTION OF CLASS 11a OPEN LIFEBOATS 221 

for the assignment, provided there was sufficient seating accom- 
modation. 

FLOODING TEST. 

(a) Boat was floated in the light condition and without 
equipment. Plugs were then withdrawn and the boat flooded 
with water imtil the water inside was at the same level as outside. 

Freeboard measured amidships = 11^ in. 

(b) Boat remained in condition (a), but with plugs inserted. 
It was then loaded to the condition when the top of the air- 
cases was awash, i.e. with a freeboard of IJ in. 

The load on board was 111 cwts., and allowing 5 cwts. for 
equipmen^- 

This would equal — - - - — =3 72 persons. 

(c) The weights were removed. Plugs were again withdrawn, 
and sufficient weights added to bring the top of the air-cases 
awash inside and outside of boat, i.e. possessing a freeboard of 
IJ in., and the inside of the boat was filled with water to the 
same level as outside. 

The load on board was 56 cwts., and allowing 5 cwts. for 
equipment — 

This would equal - _ j. => 34 persons. 

STABILITY TEST. 

It was estimated that 38 persons could be accommodated on 
the permanent structure and the remaining 16 persons on the 
upper thwarts. 

The centre of gravity of 54 persons above the " deck " was 
estimated as follows : — 

38 persons at 10 ft. above deck = moment of 38 
16 „ 2-25 „ „ = „ „36 

54 74 

C.6. of persons '^^ __ i .07 tf 
above deck "^54 

54 persons => 79*5 cwts. Equipment = 5 cwts. 
Total load =» 84*5 cwts. 

Timber support was erected in the boat for the accommodation 
of the weights (representing persons) which were arranged as 
follows : — 



222 



SHIPS' BOATS 



60 cwts. at 1'4: ft.abovedeck= 84"0 moment 
13 „ 1-3 ft. „ „ = 16-9 

Staging (55 cwts.) at lift. ,, „ = 6*05 
4 men (6 cwts.) at 1-2 ft. „ „ = 7-2 



99 
99 



Total weight =.84-5 „ 



Total moment = 114'15 



11415 
Position of G.6. of load = - -- = 1*35 ft. above deck. 

84-5 

(a) Boat in service condition, weights arranged as already 
described (see Figs. 21, 124 and 125), and so placed that the 
upper weights could be readily moved from one side of the boat 
to the other. 

A measurement batten was prepared as shown in Fig. 124. 



-nrrrrr 




_,j ^- 



:.^'-^ 




Fia. 124. 



Fia. 126. 



Stability tctits of Class IIa lifeboat. 

indicating the readings from the top of the bulwark gunwale, 
marked in feet and inches. 

Distance between reading edges of scale = 10' 5J^ 

Transverse shift of weights = T 2" 

Tlie readings from the various inclinations were recorded as 
follows : — 

Initial scale readings : Vorl, '21 WY \ Starboard, 2' 11J\ 



Cwts. *"'^'^^- 



Scale 
reudiu^. 
Port. 



*) 



/ i)/r 



r 2 



•»/ I * 



3' 1 



: Ditfereuco. 



11" 



Scalo 
reading. 
Starboard. 


Difference. 


Total. 


2' lOJ' 


ir 


2|* 



The inclinations were continued until the deck was well awash, 
and the readings noted as detailed above. Two or four men are 
usually left in the boat to shift the weii^hts in a transverse 
direction. 



CONSTRUCTION OF CLASS IIa OPEN LIFEBOATS 223 

(b) Boat in service condition as at (aj, bvi mlh the addition of 
2 tons of tcUer inside. — The amount of water to be placed on 
board was previouflly estimated by addiii;; two tons of weights 
on board and retordini,' the diSerente in freeboard. 

The weifihts were arran<;ed exactly in the positions fixed for 
the first test, but with the two toua of free water on board. The 
readings, after inclination, were noted and placed in the order 
arranged. 

From the information thus obtained, atability curves could 
be plotted and recorded. 

SEATING AND ROWING TEST. 

The boat was loaded with 54 jiersons we-aring life-jacketa ; 
38 being on the " deck." or permanent structure, and 16 seated 
on the upper or collapsible thwarts. It was aftei-warda rowed 
and steered about the dock for 15 minutes. The boat was stable 
and remained in correct trim, and there appeared to be sufficient 
room for the proper seatinf! of the total number of persons on 
board. The length of oars was 13 feet, four in number each 
aide, the thwarts being double banked. 

On the results of these teats depend whether the boat can be 
accepted for service on a vessel, and whether the constructian on 
the remaining batch of boate can be completed without any further 
alterations. 

The teste entail iinich expense and a great deal of labour, 
whidi could be obviated if standard dimensions and details of 
construction were recognised and made compulsory. 

It should be mentioned that with the modified Class IIa 
lifeboat, account has to be taken of the additional freeboard 
required over the staudai'd boat. Fiuther tests are ahio under- 
taken to ascertain if the end and side wooden bulwarks are 
watertight at the joints. 

SECTION E.— t^0N«TRUCT10N OF CLASS Ic, 11b AND 
IIo PONTOON LIFEBOATS WITH COLLAPSIBLE 
BULWARKS 

The differences between the three classes of lifeboats now under 
treatment can be seen in Figs. 3, ■') and C, 

Lifeboat** of Classes lo and liw are identically tlie same in 
method of constniction and general design, except ia regard to 



224 



SHIPS' BOATS 



the bulwarks. In Class Ic lifeboats the bulwarks are fixed, but 
in Class IIb lifeboats they are made to collapse and hinge down 
on the deck in the manner described for Class IIa open lifeboats. 



OUTSiOe BOOYA/^CV 




Fig. 120. — "Deck" plan of Clasa IIa oix-n lifeboat. 




v.. 



COLLAf>S/BLA aut.V¥A»ffS 



wcr y^£LL osCM 



l.W.L 



?\ j>frf}n>/if \i: - y- - -' »«-^- — - r~^ff f f f ' * ■'■ fl 



— ELEVATION — 



Fkj. 127. -Outline of "deck" ami well of Class IIb pontoon lifeboat. 



• COi-LAPSlBLE THrfARTS ^G_'^ ^ 



rtCfSM ^'^- ^'CH 



x--r — n — 






IS' 




Flu. 12S. -Sccti'tn of Class Uc pontoon lifeboat. 

Lifeboats of Class Ic do not lind nmcli favour with shipowners 
and shipbuiklers, owing to the additional room required for the 
fixed bulwarks, and as deck space is of such great consideration 
in a passenger vessel, we usually find that Class I. open lifeboats 





CONSTRUCTION OF PONTOON LIFEBOATS 226 

eattacLed to all the davits, and the additional lifeboats required 
make up the full complement are of the pontoon or open type 
possessing collapsible bulwarks. Boats having collapsible bul- 
warks are thus able to stow under the Class I. open lifeboats 
attached to davits, as shown in Fig. 129, or may be stowed 
inboard, one above the other, transporting arrangements being 
fitted under the boats to bring them rapidly under the davits. 
Fig. 226 and the frontispiece show how the pontoon lifeboat-a 
are stowed inboard and adjacent to the da\'it8. 

The outstanding difference between pont^>on lifeboats and the 
open lifeboats of Class IIa is to be seen in the method of providing 
the reserve of buoyancy. 

Class IIa lifeboats are fitted with buoyancy air-cases, while 
pontoon lifeboata of Classes Ic, IIb and IJc depend entirely upon 
the watertightness of their hull for buoyancy. Therefore it is 
very essential that the workmanship and materials used in the 
construction ot the pontoon lifeboats should be of the very best 
quality. 

In the first place, the timber used must be thoroughly seasoneil, 
and when completed and in service on board a vessel, they should 
be periodically and very carefully inspected. Every compart- 
ment must be easily accessible and ventilated at everj' convenient 
opportunity. 

If there were the slightest trace of dry rot in the hull of the 
boat when first completed, it would very rapidly spread under 
the conditions of a close atmosphere after the compartments 
had been closed in by the watertight deck. 

Reference has already been made when discussing the details 
of construction of ordinary pulling boats of the importance of 
having all shavings cleared out of the boat before and after 
painting. The necessity for this precaution is even gieat«r in 
the case of pontoon lifeboats, owing to the special features of 
their construction. Shavings very quickly become infected with 
dry rot mycelium, and carry the disease to other parta of the 
structure. 

The watertight deck is open to the effects of the weather, and 
in the case of wooden boats the latter has a direct influence on 
the value of the deck to keep out water, and for this and the other 
reasons mentioned, it is essential to periodically inspect the 
interior of these boats. 

The difference between the Class IIb and Class IIo pontoon 
Bfi^oats is found in the design of the deck, the former has a 
H|vU " deck and the latter has a fiush deck. The skeleton 



CONSTRUCTION OK PONTOON LIFEBOATS 227 

IfniQiea of theso two boats are practically alike, aiwl tliey 

■do not greatly differ from tlie V\aj~s IIa lifeboats in this respect, 

■Jtocept tiiat the transverec bulkheads in the pontoon lifeboata 

je watertigbt. It ia quite passible that the bulwarks of these 

mats will be of the aU trond type in future construction, instead 

Rof the combined use of wood and canvas. Very few passenger 

ftVeaeela were completed during the war except as cargo-carrj-iog 

ibipe, which considerably influenced the output of the boats 

with collapsible bulwarks. 

The hull structure of a pontoon lifeboat is divided into a 
number of transverse watertight compartments, bounded by 
L bulkheads built up in two thicknesses similar to the outside 
planking, and strengthened by longitudinal non- watertight 
ntlwatks. The size of these watertight compartments are so 
iranged that should the stnicture become damaged with two 
tompartmenta laid open to the sea, and having the full complement 
ii peisoim on board, there would still be a reserve of buoyancy 
f^nd sufiicient stability to enable the boat to keep afloat without 
d&nj!ei to the occupants. 

The skin or planking is made up of two thicknesses of mahogany 
worked in diagonal fashion, and the planks arc fitted from 
gunwale to gunwale at right angles to one another. The minim\im 
width of the planks is 6 in., and between the two thicknesses is 
laid a covering or ply of stout calico and white lead-paint. Before 
the calico is worked the plank is treated with boiled linseed oil. 
An alternative preparation for the fabric is No. 5 Navy Canvas, 
]aid in liquid marine glue. 

These tj-pes of boata are very wide and shallow, giving a full- 
formed floor, and when stoned on deck and secured with gripes 
there ia always a certain amount of " working " felt at the con- 
nection of the plank ends ; the action of a se.away would have the 
same eSect. To obviate le-akage at the keel seam, and to main- 
tain an unbroken skin to each compartment of the hull, the 
planks are fitted from gunwale to gunwale. The keel and bilge 
keelsons are fitted after the planking is complete, and the 
keelsons are formed with the usual hand grips to enable persons 
to cling to the boat should it capsize. 

" Ltindln •* Lifeboats. — Messrs. The Welin Marine Equipment 
Co., Long Island City, New York {now American Balsa Company 
Iqc.)> have specialised in the particular type of boats now 
under leview. The London firm has been good enough to 
supply the writer with a number of photographs of the various 
desigoa from which illustrations have been produced. 



238 SHIPS' BOATS 



I 



CONSTRUCTION OF PONTOON LIFEBOATS 229 

Fig. 129 ahows a 28-ft, " Lvndin " decked lijeboat stowed under 
a Class I. open liJeboat, These boats are built of heavj- galvanised 
steel, double riveted, with countersunk tinned tivete. The hull 
is decked in. The folding bulwarks are of substantial constniction, 
and when raised to the vertical position, automatically lock them- 
selves. Canvaa bulwarlts have been superseded a3 being liable 
to perish very quickly. The collapsible bulwarks when hinged 
down into the stowing position form a good foundation to stow a 
second boat. 

The hull is sub-divided into transverse watertight compart- 
ments, with raised manholes, providing access thereto, The 
manhole covers are held in place by " poit-Iight screws," 

Patent non-return valves are fitted to the deck, which quickly 
discharge water coming over the bulwark and prevent water 
entering fi-om below. 

A characteristic feature of these and other types of lifeboats 
built by the firm, is the use of a very light fender, which adds 
stability and strength to the boat. The wood used is known as 
Balsa ivood, which Ls hghter than ordinary cork, and is also 
utilised in the manufacture of life-preservers, lifebuoys, and rafts, 
and complies with the United States inspection requirements. 
These fenders are secured in place by metal straps, and can be 
removed for repair or painting in a few minutes. 

The boats are of tlie scow type, having a spoon-shaped bow 
and stem considerably raised, which gives them a great riding 
advantage in rough weather, They ofier many advantages as to 
seaworthiness, carrying capacity, and facility of stowage. The 
United States Transport Service, and many leading steamship 
lines, have adopted this particular type of boat. 

Fig. 131 illustrates the Lundin Housed Lifeboat, which is some- 
what similar in design to the " decked " lifeboat, but is provided 
with a house in which are fitted patent port hds through which 
oars-can be used tor the purpose of propelling the boat. Water- 
tight doors completely protect the passengers from bad weather. 
Automatic ventilators are fitted to the house, 
W Fig. 130 gives a general view of the " Lundin " Power Lifeboat, 
vbich embodies all the essential features necessary for this type 
of boat. It is self-righting and self-baling. The propeller is 
located and well protected in a tunnel. The boat manceuvres 
■well in the water, and can be carried in davits ; it possesses many 
advantages over the ordinary type of boat. It serves the purposo 
iof " mothering " the other lifeboats in case of necessity, an 
Sluatfatioa of which Is giveu in Fig. 133. 




fic. 132. — '■ J.undiii " power lifcbutil imdcraaing 



..^ .1 



1,„?!!S' }? f'u'"' " f"""" li'ebMt undergomR a stability test,! 
bavmg the f„lj a„„i,„ „( p,^^ accommodated witUn tll> 




" powi'r lileboiit tgwing dock-'d and o|ion li[ebo*ls. 




CONSTRUCTION OF PONTOON LIFEBOATS 23l 

house, and a ntimbec of men standing on one gunwale, whicli 
indicates the large amount of reserve stability poaseased by 
tliia type of boat, and hence her steadiness for the passengers' 
comfort, 

Wireless telegraphy apparatus completes the equipment and 
enables the boat to keep in touch with vessels and secure help 
quickly in case of need. 

While those boata are necessarily somewhat espeuaive to build, 
they are carefully designed with a view to niinimbe trouble and 
expense of upkeep. 



DECK AREA AND CAPACITY OF PONTOON BOATS. 
Classes Ic, lU and lie. 

The method of obtaining the deck area is exactly the same 
as that which is adopted for the Class IIa boat, explained in 
Part IV., Section D. and illustrated in Figs. 12(5 and 127, 

The Kni( oj surface is : 

Classes Ic and IIb ^ 3| sq. ft. 
Class lie = 3J „ 

To obtain the number of persons which the boat will carry, as 
far as the deck area will allow, we take the superficial area calcu- 
lated in accordance with the approved formula and divide it by 
the correct unit of capacity, the result will give ua the number of 
persons. 

Freeboard. — Boats of Classes Ic and IIb have a well deck, the 
area of which must be at least 30 per cent, of the total deck area. 
The height of the well deck above the water-line at all points 
must be at least equal to one-half per cent, of the length of the 
boat, thb height rising to one and a half per cent, of the length of 
the boat at the ends of the well. 

The freeboard is such as to provide a reserve buoyancy of at 
least 35 per cent. Reference should be made to Fig. 127. 

Boats of Class lie have & flush deck, and the minimum free- 
board is independent of their length and depend only on their 
depth. The depth of the boat is measured vertically from the 
nndeFside of the garboard strake to the top of the deck at 
Ttiie aide amidships, and the freeboard should be measured from 
tho top of the deck at the side amidships to the water-level 
rhen the boat is loaded. (See Fig. 128.) 



232 SfflPS' BOATS 

The freeboard must not be less than that given in the 
following table : — 

Depth of boat Minimum freeboard 

in inches. in inches. 

12 2| 

18 3| 

24 5J 

30 6^ 

For intermediate lengths the freeboard is obtained by inter- 
polation. 

The above amounts are applicable without correction, when 
the boats have a mean sheer equal to 3 per cent, of their length. 
If the sheer is less than this standard, the minimum freeboard is 
obtained by adding to the figures in the table one-seventh t)f the 
difference between the standard mean sheer and the actual mean 
sheer measured at the stem and sternpost; no deduction is made 
on account of the sheer being greater than the standard mean 
sheer, or on account of the camber of the deck. 

It is important to notice that the freeboard values given 
in the table are based on the boat floating in. fresh water ^ the 
necessary correction must be made if the boat is afloat in sea 
water. 

The boats are loaded with weights representing the equipment 
and total number of persons obtained from the capacity nile, 
taking 165 lbs. as representing one person. 

If the boats are submerged to a greater depth than that which 
provides sufficient freeboard in accordance with the table, then 
the weights are adjusted until the correct freeboard is obtained, 
and the number of persons assigned to the boat is altered accord- 
ingly. 

Draining Arrangements. — Both flush-deck and well-deck pon- 
toon boats are fitted with efficient means for quickly freeing the 
deck of water. A special type of flap non-return valve is fitted 
between the deck and planking, having rubber seatings, which 
allows the water on the deck or in the well to quickly escape, and 
at the same time prevents the water below from coming up 
through the orifices. 

The number and size of the orifices are determined for each 
class of boat by a special test. 

The arrangements are such that in the case of a lifeboat of 
28 ft. in lengtli, after it has been loaded with weights equal to 
its total complement of persons and full equipment, two tons of 



CONSTRUCTION OF PONTOON LIFEBOATS 233 

water, which haa been placed on board, must be cleared from the 
boat in (I time not exceeding the following : — 

Classea lo and 118 = 60 seconds 
Class IIo =20 „ 

For boats having a length greater or loss than 38 ft., the weight 
of the water to be cleared in the time stated ia to be directly 
proportional to the length of the boat. 

When testing the boat for freeboard, it ia usual to ascertain 
the difference in draught when two tons of weights are placed 
on board. Tliis information is noted, and when flooding the deck 
for the time teat, the correct draught will give the amount of 
water on the deck. The oriflces are covered with wood and 
weighted during the operation of flooding, aud at a signal they 
are aimnltaneously lifted for the commencement of the time test. 

An arrangement of sleeve -ports is sometimes fitted to the 
flush-deck boats in addition to the scuppers with non-return 
valves, but with the " all-wood " type of bulwarks, some better 
arraogemeat is considered necessary. 

A few decked boats have been constructed possessing freeing 
potts in the canvas topsides, provided with a canvas flap, but 
they are considered very objectionable, and should be closed 
watertight at the first opportunity by fitting canvas covering 
pieces, double sewn, and the approved arrangements fitted. 
A successful wooden hinged shutter haa yet to be designed. Few 
opportunities have been given recently to subiait for approval 
a satisfactory side fieeing port, but no doubt this will be rectified 
in the future. 

It is generally considered that in those types of boats which 
depend on the watertightness of the deck for reserve of buoyancy, 
that each boat when stowed in a tier should be separately 
supported. The weight of one boat on another is detrimental 
to the e£Eciency of the deck of the boat underneath. 

Periodical survey of pontoon boats already forming a part of 
the equipment of pasiteni;er vessels must be undertaken to ascertain 
their condition, and whether they are fit for the purpose for which 
they were orisinally intended. 

Selections are mode, and the boats placed in the water without 
any preparation by paiating or puttying. 

In each class of boat under review bilge pumps were at one 
time fitted at the ends, as the transverse compartments were not 
then made individually wat«rtight. Before the bfiat is placed 
iu the wator the bottom is sounded to ascertain if there is any 



234 



SHIPS' BOATS 



water inside, and if so it is removed as far as practicable! Hi 
small amoimt of water enters the deck or planking, means sxeM 
taken to prevent the difficulty by a thorough repair. 

At least one boat is loaded with weights conespouding to the 
full complement of persons and equipment. If water enters 
the boat after three hours, in such quantity as to become 
dangerous to the stability of the boat, efficient air-casea are fitted 
and provided in as large unltfi as practicable, allowing three 
cubic feet of air-case for each person assigned to the boat. 

The freeboard of the loaded boat, after the air-cases have been 
fitted, must not be less than that allowed by the rules in force 
when the boat was built, with the addition thereto of any 
correction that may have been made for camber or round of 
beam under these rules. J 

If the unloaded boats which have been placed in the wat^l 
show signs of leakage, after floating for three hours, they must be 
treated in the manner described. In addition to the insertion 
of the air-cases, the hull must be made perfectly watertight. 

The efficiency of the canvas topsides must be particularly 
noted during the survey as to whether they are watertight and of 
sufficient strength. 

The very best materials are employed during the constructioBj 
of these boats, and the workmanship must of necessity be t" 
highest class. 

Before construction is commenced detailed specifications a 
drawings miistJ)e submitted to the Board of Trade for approvi 
and after one set of boats is completed, severe tests must 1 
undertaken and prove satisfactory before the construction i 
further boats of the particular design can be proceeded with. 

These tests are very similar to those already fully explained 
in Part IV., Section E, when dealing with the open lifeboats of 
Class IIa, except that a further test is required to ascertain the 
efficiency of the scupper valves. They are as follows ; — 

(a) Strength ; {b) Freeboard ; (c) Flotation (at least 3 hours 
to test watertightness of hull) ; (rf) Deck-flooding ; (e) Stabihty ; 
(/) Seating and rowing. 




SECTION A.— MOTOR BOATS 

The motor launch for use on board a veBBel waa for many yeais 
considered a luxurj' equipment, and confined to one or two 
leading shipping companies, but recent experience has proved 
the necessity of an extended supply not only for the purely 
passenger type of vessel, but also for the cargo-carrier. 

The influence of the war, and the experience of many of our 
merchant seamen wlieii caat adrift many miles from land, have 
naturally increased the demand for all foreign-going vessels, 
both cargo and passenger, to be equipped with at leaet one 
motor lifeboat. 

The Anchor-Brocklebank Steamship Co. have taken a very 
commendable action iu providing atconmiodation, on most 
up-to-date lincia, for a large number of cadets on several of their 
cargo vesseb. These cadets are educated and take a sliare in 
the actual routine of the daily work and experience on board ; 
they thus receive a training of the most practical and thorough 
character. Includeil in the equipment ia a motor boat for the 
use of the cadets as a means of increasing their knowledge ui 
seamanship. Messrs. Alfred Holt and Co. and other companies 
carry power boats on several of their cargo vessels. 

A large number of our Mercantile Marine officers have been 
attached to the Fleet Auxiliary vessels, on which motor boats are 
usually carried, and the very many advantages which have been 
experienced, and the speed with which the passage can be made 
from the vessel at the anchorage to the shore, have greatly 
increased the desire to have a power boat on board, as a part of 
the equipment. 

Several countries now insist on the provision of at least one 
motor boat on foreign-going vessels. 

The boat equipment of many of our large passenger liners 
includea one or two motor lifeboats or motor lowing biats. The 
frontispiece indicates in the foreground a motor boat supplied to 




J 



236 SHIPS' BOATS 

the R.M.S. Aquitania by Messrs. Sir John Thomycroft and ( 

Ltd. Even a cui'aory ylance at the photograph will give o 




idea of the quality of constructiou, and Figs. 13i-136 show thn 
geaeral arraQgeiueiit of wiroloas equipment. 

One very great advantage with this type of motor 1 
is, that in case of disaster, it caa be utilised ^ a " mothoc] 



MOTOR BOATS 237 

ship " for towiuf; the ordinary pulling lifeboate and keeping 
them in touch with one another, and for the purpose of supply- 
ing them with medical comforts, blankets, etc., if required. 

The installation of wirelees telegraphy is an obvious advantage, 
and in tlie light of present-day experience, and the general advance 
in practical and scientiSc equipment, the dangers of an open sea 
passage are considerably reduced. The apparatus ha£ a range of 
abnat 50 miles for transmitting and consequently would be able 
to keep in constant coram imication with steamers in the vicinity. 

The .hull is built of teak or mahogany and fitted with a 
Thomycroft 4-cylinder motor of 30 B.H.P, starting on petrol and 
running on paraffin. 

Theapeed under power only is about 7 knots, and the carrying 
weight of the boat in running condition, without passengers on 

^l)o»^, about 5^ tons. 
The dimensions are : Length 30 ft. ; breadth 9 ft. 6 ins. ; 
4epth 4 ft. 6 ins. 
Generally speaking the design is probably one of the best and 
most practical proposals to meet the difficulties experienced in 
life-saving at sea. and although it is not designed to comply 
with the Board of Trade requirements for a ship's lifeboat, the 
^ equipment ia very efficient and complete, 

I Another design is shown in Figs, 137 and 138, which was 

■ constructed to meet alt the Board of Trade requirementa. 

Buoyancy air-casea are fitted in sufficient quantity to provide 

the reserve of buoyancy for the full number of persons carried 

and the weight of the motor and gear. The functions of this 

boat in addition to the larger space for the accommodation of 

I persons, are practically the same as the boat previously referred 

1. It is fitted with a X5 B.H.P. motor, giving a speed of 6 knots. 

Two motor lifeboats as described were carried on the R.M.S. 

1 Brilannic, which was lost during the war in the Medit«rranean 

[ Sea. 

The demand for power Ufeboata during the past four years 
I has beem so great that to increase the usefulness and widen the 
1 radius of action of the ordinary pulling lifeboats, portable outboard 
I motori have been fitted. 

The United States authorities stipulate an outboard motor 
I to be carried and attached to a lifeboat for towing purposes in 
lease of necessity. 

The writer has had some experience with the " Evinrude," 
Itiie " Waterman Porto," and the " Simplex" outboard motors, 
Itlie last-named being supplied by Messrs. W. Macroillan and Co. 



J 



SHIPS' BOATS 




MOTOR BOATS 



239 

1 Fig. 1^9 represents 



[ of Alloa, Scotland. Tlie photograph shown ii 
1 the 3J-^ H.-P. model, which 

is of sturdy construction and 

designed to meet the reason- 
able necessities of a ship's 

boat. One of the special 

features of this motor is the 

large nidder by which the 

boat may be easily steered, 

whether the motor is runnini!, 

■ not. Reversing gear is 

so att«d. 

The two first-named oiit- 

I board motors are too well 

, known to require any special 

I description. A large number 

[ of these are now in constant 

I operation in all parta of the 

I world. Fig. 140 illustrates 

I die Waterman Porto motor, 

' which can be easily attached 

to the transom and sternpoat 

of an ordinary ship's boat, 

the anangement of clamps is 

very simple, and so designed 

as to allow the weight of the 

engine to come on the boat's 

stem and cause no twisting 

action. 

The motor is of the 3-port, 

2-oycle type, which, owing to 

its simplicity, is considered 

most satisfactory. The crank- 
case and tiller are oast from 

a special copper alloy which 

iaspeciallyadapted for marine 

or salt water use. 

The gears are designed to 

give one turn of the propeller 

wheel for every one and one- 
half turns of the engine. 

The fuel tank is of large capacity, and carries sufficient fuel 

for several hours' use. 




I 




they appear to have given great satisfaction for the piirposs J 
intended. I 

It is generatly admitted that in a motor lifeboat the engine j 
should be of such power aa will be sufficient to allow the launch 1 
to tow other boata. The whole of the mechanism and wiling 
must be enclosed and protected from the weather, the greatest 
enemy to the internal combustion engine being dampness or spray. 

During tlie period the motor boat ia stowed in the chocks j 





for every event, and (ipportunity taken when in pott to give the 
boat a spin. Periodical attention must be given and ahould form 
part of the ordinary boat drill. 

One of the miatakea that would probahly be made in an 
ordinary cargo boat, if legislation made it necoaaary for every 
vessel to be supplied with a power boat, wonkl bo that of nej^lect. 
It requires the closest supervision, even under present circuin- 
stancee, to see that the ordinary iifeboate are kept in a iit a 



SHIPS' BOATS 

proper condition, and with the addition of mechaniccd propiil^n 

to the statutory equipment, the daily routine of attention to 
details would be increased. It is quite safe t« state that unless 
adequate care and' oversight are given to the condition of the 
motor and its accessories, the vessel is better served without a 
niot«r boat. 

The Rules for Life Saving Appliances state— 
" (1) An approved motor boat may be carried as a lifeboat 
Bubjoct to the following conditions : — 

" (a) It shall comply with the requirements for a lifeboat of 
Class I., and proper appliances shall be provided 
for putting it into the water speedily. 
" (6) It should be adequately provided with fuel, and kept so 

as to be at all times fit and ready for use. 
" (2) When the number of lifeboats is less tjjan ten, one of 
'■ them may be a motor boat. Wliere the number of lifeboats is 
'• not less than ten, two of them may be motor boata. The Board 
" of Trade may, on the application of the owner, allow a greater 
" number of motor boats to be carried, if they are satisfied that 
" the efficiency of the life-saving equipment will not thereby be 
"diminished. 

" (3) In fixing the volume of the internal buoyancy and 
" where fitted, the external bouyancy, regard should be had to 
•' the difference between the weight of the motor and its acces- 
" sories and the weight of the additional persons which the 
" boat could accommodate if the motor and its accessories were 
" removed," 

The recomtnendadoius of the Departmental Committee on Bonis 
and Davits, when dealing with the question of mechanically 
propelled boats, were as follows : — 

" We recommend that the carriage of mechanically propelled 
boats should be optional for all classes of steamships. But since 
the efliciency of a lifeboat for saving life is not diminished because 
it is fitted with a motor, we recommend that whatever be the 
number of boats carried on any ship, the shipowner should be 
allowed tlie option of carrj-ing one mechanically projielled boat 
if he so desires. 

" In the case of a vessel carrying a considerable number of 
lifeboats it would be preferable to carry a small number of 
high-powered motor boats rather than a large number of low- 
powered boata. Instead o£ increasmg the number of motor boats 
on a scale corresponding with the total number of boats caiTied, 
the size and power of the motor boats should be increased as the 



^H Durubet 
^f on each 



MOTOR BOATS 243 

In f^eneral, two motor boate 



Dumber of other boats 

on each side should be sufficient. 

The reasons which lead us thus to limit the number of motor 
boats carried are mainly connected with considerations of tlie 
efficient supervision and maintenance of a Iarf;e number of engines 
and with the difficulty of ensiuing that one or more men who are 
conversant with the working of it motor would be assigned to each 
motor boat in the confusion of taking to the boats in an emergency. 
Further, in view of the fact that an increasing number of ships 
are being fitted with wireless telegraphy, it is not desirable that 
the ships' boats should proceed far from the neighbourhood of the 
disaster. The motor boats would be used for keeping the other 
boata together and generally shepherding them, rather than for 
towing a number of boats a long distance. In certain trades, 
of course, they could go reaaonable distances in search of succour. 
Also one or two powerful motor boat*) might bo of service in 
rendering assistance in bad weather on a lee shore. In these 
circumstances we recommend that the motor boats carried should 
be as large and as powerful as possible, having regard to the 
size of the ship and the means available for handling and launching 
such boats. 

" As to the type of engine which is moat suitable for this 
purpose it may be said that ^team is of little value owing to the 
delay involved in starting the engine. The use of petrol in bulk 
is viewed with disfavour owing to the risk of fire and explosion. 
On tlie whole, therefore, we recommend the type of engine known 
commercially as the paraffin engine. This engine is simple, safe, 
and rehable, and there are several satisfactory patterns on the 
market. Even with this engine, if iwrafliii alone is used, con- 
siderable delay iji starting the engine may result from the difficulty 
of heating the vaporiser under unfavourable conditions of 
weather. The use of a small quantity of petrol, however, 
niatorially facilitates the starting, and we have seen a syBtem 
of petrol starting which obviates the ordinary dangers arising 
from the use of petrol in bulk. The petrol is carried in email 
hermetically-sealed cylinders which contain one starting charge 
only, so that the possibility of leakage and evaporation ts 
minimised. 

" Special attention should be given to making the ignition 
gear damp-proof, and the casing of the engine watertight. 

" Evidence has been put before us which shows that fuel 
could easily be carried to cover a radius of 100 miles. This 
quantity of fuel should be the minimimi, 



SHIPS' BOATS 



244 

" Iq order to ensure that the engines are always in working 
order, they should be started up at every boat drill. Steps should 
be taken to secure that this rule shall always be observed. In 
order that no damage may result from starting the cngiDe on the 
veasel's deck, provision should be made for proper water circula- 
tion in such cases, when the design of the engine necessitates 
water-coo Itn}^." 

Construction ol Hull— There are very few features connected 
with the construction of the frame and the method of working 
the planking, which have not already been explained in full 



■ 
I 



detail in the section dealing with the construction of ordinal] 
pulling boat**. 

The planking of the smaller type of motor launches is sum 
times worked on the " cliuker " method ; but the great majoritn 
of ships' motor boata are planked on tbe " car\-el " or " doubf 
skin " system, A Hush surface on the outside ofiers lee 
resistance, and gives the best underwater form for the moa 
satisfactory speed results.- The larger type of motor boats i 
eonstructwl on the " carvel "' principle in many caseSj but is 
variably the " double-skin " planking is used, as in this casa { 
naturally follows that the hull is much stronger and better able ti 
withstand the climatic changes of atmosphere. Each of tha 
methods has already been fully described in Section A of 1 





L 


1 


L 


p ...„„ J 

^B IV., and it will serve ho useful purpose to refer to the question ^H 
^B again in any detail. ^H 
^m Practice varies even in the limited area of the Firth of Clyde, ^M 
^B where in one yard the section moulds are so arranged as to allow ^| 
^B the motor boat to be constmcted upside down, in similar fashion ^B 
^V tc> thiit which in atlopteil whi-ri Ihi' fiinin' is c'lmplete and the ^M 


H Via. 142.— Mo 

V planldng ha 

collapsible b 

The boat 

planldng ha? 

^ Figs. 141 

^■.construction 

^B diagonal sys 

■^ (ore-aad-aft- 

The phot 

JdcGnier an 


P^ 


on by Mo8s™. 

eboate with 

on until the 

in course of 
rked on the 
■, fitted in a 

■is of Messrs. 
ated on the 


' l5^a^> 


tor boat. Fore end view. Uiiddr oouslructi 
MuGruer and Co.. Ltd., Clynder, Siotland. 

3 commenced, in the case of the lil 

ulwarks. 

is not turned over into its upright poait 
been completely finished and fastened, 
and 142 illustrate a 20-ft. motor boat 
having an inner skin of mahogany', wi 

■em, and an outer skin also of mahogan 

direction. 

ograph was taken in one of the boat-she 

1 Co., Ltd., of Clynder. beautifidly situ 



246 SHIPS' BOATS 

shoreti of the Garelocli, Scotland, &iid witliin easy accms to boi 
of the best timber in the country. 

The work turned out by this firm is of the very highest class, 
and the name, coupled witli that of Messrs. Fyfe of Fairlie, 
well known throut^hout Great Britain among shipbuilders and 
superintendents, as being the hall mark of excellence. The writer 
hat*, therefore, taken the libeity to insert in this section a complete 
specification for the hull of the standard 22-ft. motor boat^^ 
supplied by Meaara. McGrucr and Co.. Ltd., and which conformft] 
to all the requirements of the Board of Trade. 

The lines of a motor boat, in the first place, have to be veiy 
carefully conaidered. not only in their apphcation to certain 
features of importance considered in the Board of Trade Instruc- 
tions, but more especially to the question of speed and displace- 
ment in their relation to stability, and the service for which th«J 
boat is intended. 

It therefore follows that moul<i3 have to be made to ths 
faired lines on the floor, in the manner described in Section A ol 
Part IV. 

It is very essential that the combinations which form the frame 
or backbone of the boat should be specially considered in relation 
to the stresses they will be called upon to resist. 

If the engine is installed amidships, then it becomes necessary 
, to stiffen the boat up longitudinally to counteract the tendency 
to sag, by fitting a substantial keelson. 

In the smaller type of motor boat, owing to the desirability 
of keeping the eufrine as low down as practicable for the purpose 
of stability, there is insufficient space between the fly-wheel and 
hog-piece to allow for the fitting of a keelson ; the longitudinal 
strength in this case is, therefore, maintained by fitting two bilge 
or side stringers of heavy scantlings. 

Special attention is given to the combination of materiala 
and fastenings in way of the stempost and deadwood, to takej 
the thrust and continual vibration set up by the propeller and 
shaft. 

Again, the important matter of how the lifeboat is to be lift( 
and the position of the lifting-hooka to suit the particular ty] 
of davit fitted on the vessel, must receive close attention. 

If at all practicable, fixed lijting-liooka should he fitted, but' 
the design of the boat may be such as to prevent this being done, 
and in that case there is no alternative but to fit chain slings. 
Proposals have been put forward to supply wire slings, but there 
is always an element of doubt as to the continued efficiency olj 



I 




MOTOR BOATS 



247 



these, having legoid to the effect of the weather and the possibility 
of corroflioit. 

iniera is no donbt that chain alinga support the boat and 
diBtadbute die Btceeses along the full length of the hull in a mote 




Fifl, U5.— Forward oomU nation*. 
Conatniotjon of end combinatiooe loi s 22-tt. motor boat. 



satisfactory way than do fixed hooks ; but, on the other hand, there 
ia not the steady control with the slings which is associated 
with filed hool<s,evca with steadying chains fitted to the former. 
The tendency is for the boat to move from the upright position by 



248 



SHIPS' BOATS 



the shifting of the occupants of the boat or by the movement of the 
equipment. The point is worthy of consideration, particularly 




f/lUAfG ^*CC£ 



Fig. 146. — Midship section of a 22*ft. motor lifeboat. 



r\ 



I 




CAP^//fO 



'^ ' ¥ : 'tJ V I 









when one has to provide for the difficult circumstance when the 
boat may be filled with panic-stricken passengers. 

The drawings shown by Figs. 14^145, 
give the disposition of fastenings for a 
22-ft. motor boat, having fixed hooks to 
suit " Welin " davits, which lift the boat 
at a distance of about 17 in. from the 
extreme ends. 

The sternpost, stem, deadwoods, and 
transom knee, should be secured from 
material grown to shape and of the very 
best quality. 

It is somewhat difficult at times to 
secure the after deadwood in one piece, 
and the difficulty is obviated by carefully 
checking the details together and strapping 
with side pieces. 

Sufficient material must be left in the 
deadwood to give support to the pro- 
peller shaft and to house the stuffing gland. 
Double securing bolts should be fitted to 
the keel and deadwood, and arranged to 
clear the shaft without weakening the 
combination. Provision should be made 
for withdrawing,' the shaft by fitting a hinged metal support 
between the heel of sternpost and transom, as shown in Fig. 143. 






I 



Pvaarfi 



H^ 



Fio 147. — Details of gun 
wale for motor lifeboat. 



MOTOR BOATS 



t 




i 
I 

The midship section of the 22-ft. motor boat is shown in 
Rg. 146. Care must be taken before the construction is 



SHIPS' BOATS 

commenced to ascertain the space that will be taken up by the 
bucyancy air-cases, having in view the additional buoyancy 
which is required to support the weight of the motor and 
its accessories. It is a very difficult problem to house these 
air-casea without encroaching on the available space for seating, 
working around the engine, and locker accommodation. Air- 
caae'i must not be fitted on the floor of the boat, and athwartehip 
air-cases are considered objettionable, but are difficult to avoid. 

The method of arriving at the correct cubic capacity of the 
buoyancv air-cases to be fitted, ia dealt with in detail under 
ScctionCof Part VI. 

Fig. 147 shows the detail of gunwale and nash-strake c<wi?»ino- 
lion. The toimdini; of the capping-edge, and the fitting of a 
fillet piece between capping and wash-atrake, give a pleasing 
finish to the boat. 

Fig, 148 shows in outline the general arrangement, and the 
following specification indicates the scantlings of the various 
component parts, of the 22-tt. motor lifeboat already referred to. 
There is seating accommodation for 17 persons in this particular 
boat. 



SPECIFICATION FOR A ST.VNDARD 22-ft. MOTOR 
LIFEBOAT, 

C'ON.STRUCTED BV MESSRS, McGrL'ER AND Co., LtD.. Ci.YNDER, 

Dumbartonshire. 

I}ifnenaions. 

Length {between outside of plank rabbets) . . 22 ft. in. 

Length overall (about) 22 ft. 4 in. 

Breadth 7 ft. in. 

Depth to top of gimwale capping 2 It. 10 in. 

General. — The boat to be built under cover and protected from 
weather during constniction. Except where otherwise stated 
all fastenings to be of copper and to Board of Trade requirementa. 
All materials used to be of the best quality. The timber to be 
clean grown, well seasoned, grown to fonu where required, and 
free from defects. All iron and steel work to be galvanised. 
To be of superior workmanship, and all materials to be of the 
best quality. The life-lines round boat to be of good yacht 
quality white manila. OJiinwaies to be well finished in every 
respect, the sheer of the boat to be neat and " eye-sweet," and 



MOTOR BOATS 251 

in accordance with the standard requirements of 4 per cent, of the 
kngth. 

The motor boat during construction will be under the survey 
of a ahip surveyor of the Board of Trade. 

1. Ked. — Canadian rock elm in one length, sided 3 in., 
moulded 4 in. 

2. Hog. — Canadian rock elm in one length, sided 5 in., and 
moulded 1 in., clench fastened through keel with suitable copper 
naik and washers. 

3. Slem. — ^British oak, well grown to form, sided 3 in., and 
moulded 4 in., scarphed to keel, and fastened with copper clench 
bolts and nails as required. 

4. Apron. — Euglirfi elm, moulded 3| in., and sided to fay 
its whole thickness against the planks of boat, fastened with 
suitable clench nails and bolts. 

6. Fore Deadtoood, — British oak grown to form, moulded and 
sided to fay against the plank throughout. Fastened with 
suitable copper clench nails or bolts. 

6. StemjK)st. — British oak, grown to form, sided 5 in., and 
moulded to suit the form of boat, fastened with suitable copper 
clench nails and bolts. 

7. After Deadiwod, — English elm, sided 5 in., moulded as 
required, and suitably fastened with copper bolts. 

8. Transom Knee. — ^British oak, grown to form, sided 3 in., 
and moulded as shown on the plan, fastened with copper nails 
and bolts. 

9. Transom, — English elm, 1 J in. thick with bent cant timber 
against the inside surface. Clench fastened to transom knee with 
copper nails. 

10. Planking, — Carvel built of Honduras mahogany f in. 
finished. Fourteen strakes each side. Six scarphs each side to 
be allowed. Fastened through lands with clench nails No. 12 
gauge, and through timbers with No. 10 gauge. 

11. Timbers, — Steamed, of Canadian rock elm, spaced 5J in. 
centre to centre, sided IJ in., moulded | in. To be in one length, 
except at the ends where they will be mortised into the deadwoods. 

12. Gummles, — Canadian rock elm, in one length, 2 in. deep 
and 1| in. wide, the space between the timbers to be filled in 
with pine, and fastened through each timber with copper clench 
nails. 

13. Quarter Knees and Breasthook. — British oak, grown to 
form, to be fitted to cross-piece and gunwales, and fastened with 
copper clench nails and bolts. 



SS3 SHIPS' BOATS V^^^^H 

14. Rinngi. — Canadian rock elm, in one length, etuAi side 
tounded on inside eddies, and fastened through each timber with 
copper clench nails. 

15. Ruijters. — Canadian rock elm, in one length, each side, 
IJ" X li', fastened through each timber with copper clench naiU. 

16. Bilge Stringers. — Canadian rock eUn, 3" x IJ', fitted full 
length ot boat in one piece, and secured to every alt«mat« timber 
with copper clench nails, gauge 10. 

17. Capping to Gunwales. — Canadian rock elm in one length, 
f in. thick, and broad enough to cover gunwales, timbers, sheer 
fltrake, and to project | in. over sheer strake-, where it will be 
rounded to form bead moulding. To be fastened with copper 
sjiike nails, 

18. Deck Bea»/w.— British oak, sided 1 in. and moulded 1 J in. 
at centre, and tapered towards ends. Round of beam to be 
3 in. in 6 ft. A ledge to be fitted under beams at boat's aide, 
through-fastened at each timber, the beam ends to be clench- 
fastened to this ledge. 

19. Deck Plank. — Teak or mahogany, | in. thick and 3 in. 
wide. To be fastened to beam with brass screws and doweUed. 
Seams to be caulked and paid with marine glue. 

20. Coaming to be worked as shown on plan, Canadian rock 
elm, I in. thick, fastened with brass screws and doweUed. To be 
further secured with six gun-metal knees secured to outside 
coaming and capping. Depth of coaming to be 6 in. above 
gunwale capping, 

21. Jtfotor Bearers. — Selected pitch pine or fir, sided 2J in., 
moulded to suit engine and form of boat. Not less than 9 ft. long. 
Fastened with through copper bolte about 12 in, apart. To be 
further strengthened transversely by an oak floor at each end of 
the engine, the floors to be clench-fastened through keel and 
plank, a clench bolt to go through bearer, floor, and plank. The 
space under the engine to be filled in with pine to the height of the 
timbers and lined with fourteen-ounce copper to form an oiltight 
saveall. Motor to be installed in accordance with best practice. 

22. WaUrtight Bulkhends. — ^Teak or mahogany, two skins, 
each I in. thick, with oiled calico between. Rtt«d at each end 
of the motor space, and made watertight up to the height of the 
thwarts. Each bulkhead to have suitable drain valves. 

23. Thwarts and Benches. — Teak or mahogany, 1 in. and | in. 
in thickness respectively. To be supported with ebn or oak 
knees where necessary, and fastened with brass screws. 

24. Stem-sheets and 6Vfl/i*JM/8.— Laid on fir bearers 2'Xl'. 



^1^. 



MOTOR BOATS 



253 



Teak or lutiliogany side pieces J iii. thick, fastened down with 
brass screws. Teak or mahogany skirting worked above side 
pieces and screwed to timbers. Two poiiable elm or teak J in. 
mesh gratings fitted between side benches. 

25. Bottom Boards tn Fore Cockpit. — Red pine or fir J in. thick. 
Mode portable where necessary. 

26. Rudder mid Tiller. — The rudder to be EngJiah ehn in 
one piece, 1 } in. thick, bearded to I in. at the after edge. The 
head to be oval, formed by | in. cheeks. A gun-metal cap to be 
secured on top through which the forged-iron tiller with turned 
wood handle will be fitted, and made secure with ornamental 
nuts. .Rudder hangings to be gun-metal. 

27. LiJUng Hooks and Keel PifUes.—^o be of the fixed type 
and in accordance with Board of Trade requirements. 

28. iSfemtand.— Galvanised wrought iron. Skeg to be gun- 
metal. 

29. Staves. — Ensign and pendant staves to be of ash, IJ in. 
meter. 

. Canvas Gear. — Boat cover and canopies to be a good fit. 
11. Motor Casing. — ^To be teak, with sliding panels and hinged 
I lids. 

32. Towing Bollards. — Oak towing bollards to be fitted on 
each side of stem, and one each side of bow, with metal pins ' 
through the centre of each bollard. 

33. Buoyancy Air-Vases. — Copper buoyancy tanks of sufficient 
capacity made to fit the boat's sides and cased with teak or 
mahogany. 

3i, Storm Hoods. — Two storm hoods, each fitted on three 
I in. galvanised iron rods, hinged at coaming, and laced to brass 
hooks and eyes on coaming. 

35. Deck FiUitujs. — Two galvaui.sed iion mooring bollards. 
Four galvanised iron fairleada. 

36. Paintiwj. — Three coats of best paint or varuisli, inside and 
outside to approval. The planking of boat to be sandpapered, 
fmd paintwork to be first class. Decks and internal fittings two 
coats of varnish. 

37. Weig}(t. — Approximate weight complete=2'2 tons. 

38. Seating Copaci/y.— Proper seating accommodation is to 
be provided for 17 persons. 

39. Notes. — Cast brass plates with ship's name in one-inch 
letters to be screwed to etern, anil similar brass plate with 
Port of Registry fitted at bow. Portable rope fender fitted 
afcbow, 



254 SHIPS' BOATS 

40. Outfit, — In accordance with the requirements of the life- 

Saving Apphances Rules, viz. : 
Six oars for rowing. 

One oar for steering, blade painted green. 
Two plugs with chains. 
Eight crutches, including one for steering oar, attached to 

boat by chains. 
Sea anchor, canvas, with 20 fathoms of tripping line and rope 

trailer attached. 
Bailer. 

Two-gallon galvanised iron bucket. 
Painter, 20 fathoms in length. 
Boathook. 
Water breaker or galvanised iron tank, holding one quart for 

each person that the boat is deemed fit to carry. 
Suitable metal dipper, tinned, attached to breaker by lanyard. 
Two hatchets, one at each end of boat. 
The rudder, tiller, bailer, bucket, and hatchets to be secured 

to the boat by sufficiently long lanyards. 
Copper or metal lantern, trimmed with oil and sufficient 

to bum for eight hours. 
Liquid compass in binnacle, to latest requirements. 
Air-tight case to hold 34 lbs. of biscuits, and spanner attached 

for opening plug. 
One gallon of vegetable oil. 
Oil distributor, to be attached to sea anchor. 
One dozen self-igniting red lights in watertight tin. 
Box of suitable matches in watertight tin. 
The following are provided, if required, in addition to the 

statutory equipment : — 
25 lbs. galvanised anchor, with 25 fathoms of 3jV, in. galvanised 

chain. 
One three-light combination light (masthead, port, and 

starboard). 
One small rotary pump and hose. 
One chemical fire extinguisher. 
One box of sand with scoop. 
Mechanical syren. 

General Requirements. — It is quite beyond the intended 
scope of this treatise to deal in detail with the question of the 
internal combustion engine, as many valuable and helpful text- 
books have already been written on the subject. 



MOTOR BOATS 

It 18, therefore, the purpose of the writer, to deal only with 
cei'tain important esaentiaifl affecting the instaUation of petrol 
and paraffin engines in motor Hfeboats. 

Before construction is conunenced on the hull, there ere 
certain general conditions which miiBt be strictly observed. 

The BcantUngH and full detailed specification of hull, together 
with particulars of machinery, oil tanks, and class of oil to be 
used, must be submitted to the Board of Trade for approval, if 
the lifeboat is to form part of the statutory equipment of a vessel. 

It is considered preferable that the space occupied by the 
mot«r. fuel tanks, pipes, etc., should be situated at the after 
end of the boat, for the better protection of the passengers or 
occupants. 

The motor space is separated from the space occupied by the 
passengers or crew by a watertight bulkhead. In the particular 
case where the engine is fitted amidships, and the majority of 
^H motor launches are thus arranged, bulkheads are placed at each 
^F end of the motor space, and made watertight to at least the height 
of the seats. These bulkheads are usually made oi two thick- 
nesses of teak or mahogany, with a calico or canvas fabric between, 
well bedded in marine glue or treated with boiled linseed oil and 

1 white-lead paint. 
Installation of Motor.— The power of the engine must be 
snitable to the size of the boat. (Shipowners have often stipulated 
a speed out of all proportion, which has practically resulted in the 
building of a boat to suit the ty|}e and weight of the machinery, 
instead of making proper provision for the accommodation of the 
occupants, and installing an economical type of engine poesesaiug 
a reasonable power which will develop a speed of 7 or 8 knots. 
A 30 B.H.P. 4-cyhnder motor installed in a 30-ft. hfeboat 
gives a speed of about 7 knots. A 20 B.H.P. 4-cyliuder motor in a 
28-ft., and a 12 B.H.P. 2-cylinder motor fitted in a 22-ft. motor 
lifeboat would give about the same speed. 
To secure a greater speed would mean the titling of a much 
larger motor, more capacity for the fuel tanks, greater weight, 
and a smaller number of passengers accommodated. 
Particular care must be exercised in fitting substantial bearers 
under the engine, well secured to the hull. The motor should be 
kept as low as possible in the boat. 
The cylinders are tested by water to twice the maximum 
working pressure to which they will be subjected under service 
conditions, and the silencer and the exhaust pipes to at least 
one-fouith of the pressure apphed to the cylinders. 



356 SH1P8' BOATS ^^^H 

Prevention of Oil Leakage.^ — The niotoi standH iii a metal trsy,fl 
which ia forniwl so as to admit of being readily cleaned, and everyfl 
care ahoidd be taken by the fitting of suitable drip pans where'l 
required, to prevent the woodwork fiom becoming saturatod I 
and the oil spreading through the bilges. I 

The floor boards are made portable to render easy access to I 
the bilges for inspection. M 

Receptacles, fitted with wire gauge coverings, are provided.B 
to catch any overflow of petrol from the engine. I 

The greatest safeguard against explosion or fire is cleonlinesS).! 
and every precaution should be taken when installing the motor, I 
to see that the woodwork and bilges are kept free from oil refuse..! 
All tanks and a^tsociated fittings must be perfectly tight. I 

If a paraffin tank is installed, no cocks should be fitted excepti 
for the motor pipe connections. ■ 

Insulation. — It may be necessary, in way of excessive heatfl 
from the cylinder heads or exhaust pipe, to aheath the surround-l 
ing woodwork with metal. It is also very desirable that the! 
wooden flooring in way of the motor should be sheathed in tbiSB 
manner. I 

Carburettor. — Connected to the cylinders is a supply pipftV 
leading fi'om the carburettor. The function of the carburettor,! 
briefly explained, ia to receive the petrol from the fuel tanki 
through a supply pipe fitted to the bottom of the float chamberi! 
the admission of which is regulated by a needle valve having mm 
spindle connected to a float. I 

By the action of weight" operating on the float and valve,! 
fuel is alhiwed to enter the chamber regularly and remain at aA 
constant level. Connected to the float chamber is a pipe witb^ 
a jet, situated just above the level of the fuel, which is led into a 
mixing chamber, and as soon as the engine is started, air ia drawn 
by suction into the mixing chamber. At the same time fuel is 
drawn from the jet in the pipe leading from the float chamber,.] 
and in association with air it becomes vaporised owing to ila 
volatility, and remains so during its passage to the cylinders. 

The proper proportion of fuel vapour and air is obviousljn 
very important, in order to produce the best results from th« 
point of view of economising fuel without loss of power. 

The controlling of the mixture in suitable proportions fi 
the basis for the different characteristics of the many useful tyj 
of carburettors now on the market. 

Carburettura must be of sucli a type that when the I 
is 8t<)pped the supply of petrol to the carburettor is shut ofij 





MOTOR BOATS 



aiitomatically, but, iu auy case, means should be provided to 
prevent an overflow of petrol from the carburettor into the boat. 
The pipe which conveys the petrol to the carburettor is solid 
drawn copper, and provided with flexible bends, Iiaving a cock 
or valve fitted at each end of the pipe, one being on the tank, and 
the other on the carburettor or float chamber. All joints and 
couplings are made so aa to be always accessible and kept oil- 
tight. 

Paraffln Motors. — Petrol motors are usually fitted to the 
aniallest type of motor boats, but where a wider radius of actiim 
is necessary, which involves a larger quantity of fuel, the installa- 
tion of paraffin engines is much to be preferred. The latter have 
the advantage of using a fuel which possesses a much higher 
flash point than petrol, and is, therefore, not so liable to create 
danger to the passengers, 

In a ship's lifeboat it seems essential to resort to the necessity 
of maintaining a small supply of petrol for tlie purpose of starting 
the motor, to enable the boat to clear from the ship as quickly as 
possible, instead of having to wait until the cylinders become 
heated by the application of blow-lamps, 

In petrol motors the fuel is vaporised at ordinary temperatures, 
being verj' volatile, and when brought into contact with a current 
of air created by the suction of the motor, it remains in a condition 
of vapour. When the petrol and air enter the cylinders in proper 
proportions, they form together an explosive mixture. 

Paraffin will not remain in vapour form when mixed with 
cold air, beini; not bo volatile as petrol, and it becomes neccasar\' 
to arrange for the fuel to be sprayed into the cylinders 
after the latter have become heated, or to bring it into a 
gaseous condition before entering the cylinders by means of a 



Petrol is first appUed to start the engine until there is sufficient 
heat created in the exliaust pipes to vaporise and bring the 
paraffin mixture into a condition of combustion. The petrol 
supply is then shut oS, and the motor continues running on the 
paraffin. 

Alternatively the inlet pipe or vaporiser can be heate<l by 
blow-lamps inserted so that the flames pass round the heating 
chambers until a temperature of about 140° F, is reached, when 
the conditions are such as to allow the engine to start and to 
keep running by the action of the heated exhaust vapour from 
the cylinder around the walls of the heating chamber of the 
vaporiser. 



258 SHIPS' BOATS 

A 28 B.H.P. motor takes about ten minutes to heat by blow- 
lamps before it is in a condition for starting. The flame from 
the blow-lamps must be enclosed. 

Hot Bulb System* — Briefly explained, this consists of a bulb 
attached to the cylinder, which is heated. The paraffin is 
then sprayed direct into the interior of the bulb, an^ becomes 
vaporised. There is a valve connection to the bulb, through 
which air is drawn, the combination of air and vaporised fuel 
producing the explosion. The size of the bulb depends on the 
compression of the engine. 

Very few motor launches are fitted with the hot bulb system ; 
it is practically limited to vessels which are run for commercial 
purposes. 

Sufficient information may be gathered from the rough 
description of the various systems in operation, to feel con- 
vinced that, taking the circumstances into consideration, a power 
lifeboat should be installed with a paraffin-burning motor, but 
fitted with arrangements for starting the engine on petrol. 

Fuel Tanks. — The petrol tank must be large enough to obviate 
the necessity of carr}nng a supply of petrol in spare cans. It 
should be substantially made and so arranged that, when being 
filled, petrol will not escape and find access below the deck. 

A wire gauze diaphragm is fitted to each inlet and outlet of 
the fuel tank, made in such a manner as to be easily removed for 
cleaning and inspection. 

The open end of the inlet pipe is led to the atmosphere above 
the deck, as the air- and gas displaced when filling the tank may 
be an explosive mixture. 

A feature in connection with the motor and all its accessories 
is that all the pipes and fittings must be perfectly tight, to prevent 
the escape of petrol gas. 

If the oil tank is of iron or steel it is galvanised and usually 
tested by water to a pressure corresponding to a head of water 
of at least fifteen feet. 

The fuel tank in small motor boats, and in boats fitted with 
petrol tanks for starting purposes, is arranged at a convenient 
li(»4ght to allow the supply pipe to have an easy lead and give a 
steady and constant delivery by the force of gravity. Where 
the horse-power of the engine is great and the radius of action 
of the motor boat is large, then it becomes necessary to carry an 
increased (jiiantity of fuel. 

It is essential from the point of view of stability, that all 
weiglits should l)e carried as low as possible in the boat, therefore 



MOTOR BOATS 



^^Rtt is advisable to keep the fuel tank well down below the deck 
^^ ends, and in these circurastancea it is an advantage to fit a system 
of forced feed, or a means of supplying fuel to the carburettor 
under pressure. 

Water Cooling.— Water is pumped into the cylinder-jackets for 

■ cooling purposes. It is essential that care should be exercised 

I when deciding on the position of the water inlet pipe in order to 

[ preserve a constant supply through easy leads, and that the 

intake is never, at any time, out of the water. 

It is, of course, necessary to fit a strainer at the inlet to prevent 
weeds choking the supply pipe, and also a seacock close down to 
' the hull. 

The exhaust pipe, which carries away the discharged vapour 
\ from the cylinders, becomes very hot, owing to the gas reaiaining 
at a very high temperature. With a wooden lifeboat this becomes 
irious consideration, and effective means should be pnivided 
for water-cooliug or lagging the exhaust pipes, which are led out- 
board above the water-line or down through the bottom of the 
boat, and the gases discharged into the water. 

Reverse Gear.^ Adequate provision is made to allow the boat 
to go astern. Sometimes the arrangement simply conaista of 
reversing propellers, the action of which is to reverse the piteh 
of the blades, but maintaining the same direction of rotation. 

The usual practice is to supply a gear actuated by a clutch 
which directly alters the rotation of the shaft. There are many 
satisfactory types uf reverse gear now on the market. 

ISnlflon-^The greatest enemy tfl the internal combustion 
engine is r2am/>. The ignition fittings and wires must therefore be 
, efficiently protected from moisture, to enable theoi to be of 
I service after a period of disuse. The machinery, or engine, 
, must be closed in or properly protected from the weather and 
L spray. 

When the vaporised mixture of fuel and air has been com- 
I pressed by the action of the pistims in the cylinders, the explosion, 
or power which drives the engine, is produced by aa electric spark 
generated by an electric battery, or accumulators, and an induc- 
tion coil, or by what is now universally used, a magneto. 

The feature of the induction coil is to transform the low 
r volta^ current of the accumulators to a high voltage in order to 
I produce the electric spark for ignition purposes. 

The distance between the terminals through which the spark 
I jumps, is termed the spark gap. Mechanical means are fitte<l 
rnnTk the caiushaft so as to make contact with the switch, and 



SHIPS' BOATR 






piodnce s spsrk st the correct oiotneDt for the ignitMia 
oompresaed vapour in tJie cylinder. 

The magneto is practicallj a snutU dynamo ot medumical 
means of gaierating eleMricity, instead of with the aid of 
chemicaU. 

Sometimes a combination of the two systems is used, the 
accumidatoiB being fitted for the purpose of starting the engine. 

With the high tension system of ignition, there is alwa^-s tie 
danger of leakage, and all wiring must be ven,- carefully initiated 
and protected from moiHture. 

Where the wires are led into the cylinder to produce the 
ignition spark, there is fitted what is termed a gpark plfig. which 
provides proper protection to the wires, enables them to 
withfltand the effect of the explosion, and give the necessary 
amount of insulation. 

Lnbrle&tlon.— The question of a satisfactory means of hibri- 
eating the bearing surfaces of the machinery is one of importance, 
owing to the speed of the motor and the generation of a very high 
temperature. 

One system is by the supply of oil to the crank case, and the 
action of the rotating connecting rods simply splashes the oil 
over the various bearings. This method can only be considered 
successful when the motor engine is kept nearly level with the 
water-line. In the majority of cases the cylinders are inclined, 
and it then becomes necessarj' to fit the ordinary drip or pressure 
feed systems. 

VBntilatlon.^\Vhen the motor or the petrol tank is situated in 
an enclosed space, special precautions should be taken to pro\'ide 
an efficient means of ventilation, by the fitting of cowls or other 
suitable ventilators, one of which should be carried down to the 
lower part of the enclosed space. The combination of the two 
ventilators will prevent the accumulation of oil vapour in the 
lower part of the boat. 

Fire ExtingulaUng Appliances.— Reference has aheady been 
made in Section B of Part III,, to the use of non-infiammable 
wood in connection with the construction of the bearers or 
seating for the motor, and the covering casing. 

The general expression of opinion is that this particular 
wood serves its purpose well, and its incorporation into the 
structure is certamly a precautionary means against the spread 
of fire. 

It is usual to provide one or two chemical fire extinguishers, 
tlie number depending on the size of the boat. These are fitted 




MOTOK BOATS 261 

ia a rack near tho eugiue ready £or mime«liiitb__iiBe. In additiun 
to the extinguisliers, a box of sand not less than one cubic foot in 
capacity, is provided together with a suitable scoop for applying 



General Remarks, ^The quality and size of tho shaft have 
to be considered in relation to the power of the motor, and this 
is a point which rnuat be given due prominence in the specification, 
as the Board of Trade oSicials may consider it is too small, and 
if construction on the stempOst and deadwood has commenced, 
then there is trouble. The shaft is tested for ductiUty and 
tensile strength ; it is usually made of phosphor bronze. 

Particular att«ntion must be paid to the Heatings of the engine, 
gear box, and thrust block, in order to preserve the ahgmnent of 
shaft. It iH of the utmost importance that the first consideration 
should be the strength of the fiadie combinations to prevent any 
movement when the boat is subjected to hogging and sagging 
stresses from wave motion. There is constant difficulty to secure 
a smooth running engine if the foundation or seating is insecure. 
In this respect, from the writer's point of view, it is an undoubted 
advantage t<i the boat when the firm constructing the hull is at 
the same time able to build and instal the motor. The trades are 
quite separate and distinct, but many difficulties are often 
avoided when the engineers are given the opportunity to cany 
through the installation; the opinions of both trades are 
necessary to secure the best results. 

The best of material may be worked into the construction 
and the highest standard of workmanship brought into operation, 
in fitting out a motor lifeboat with all the latest and most efficient 
appliances for propulsion, but unless constant care is exercised 
in periodically overhauling, lubricating, and keeping the motor in 
trim, while the boat ia in service on board a vessel, the value of 
the launch as a life-saving appliance is very small. 

The danger of neglect would be more pronounced in the 
case of a " power ' than in an ordinary pullmg boat, hence the 
hesitation on the part of some people to limit the number of 
motor boats on a large passenger vessel. 

The equipment supplied to a motor lifeboat is the same as 
that appropriated to a Class I. open lifeboat, except that sails 
may be dispensed with, and as it is usual to fit a proper rotary 
or plunger pump tor keeping the bilges throughout the length 
of the boat free of water, it seems unnecessary to supply the bailer 
as detailed in the instructions. 



I 




LLOYD'S RULES FOR THE SURVEY OF INTERNAL COM- 
BUSTION ENGINES (OTHER THAN OF THE DIESEL TYPE) 



GENERAL. 

Section 1. — In vessels propelled bv internal combustion 1 
engines the rules as regards machinery will be the same as those I 
relating to steam engines, so far aa regards the testinf{ of material 1 
used in their construction, and the fitting of sea connections, I 
discharge pipes, shafting, stem tubes, and propellers ai 
concerned. 

CONSTRUCTION. 

fiection '2. — 1. The following points tdiould be observed i 
connection with the design of the engines ; — 

2. The shaft bearings, connecting-rod brasses, the valve gear, i 
the inlet and exhaust valves must be easily accessible. 1 

3. The reversing gear and clutch must be strongly constructed I 
and easily accessible for examination and adjustment, 

4. In engines of above 60 B.H.P.. which are not reversible, ] 
and which are manoeuvred by clutch, a governor or other arrange- I 
ment must be fitted to prevent racing of the engine when I 
declutched, 

0. Efficient positive means of lubrication (preferably sight J 
feed) must be fitted to each part requiring continuous lubrication, 1 

(i. If the engines are of the closed-iu type they must be ra I 
fitted that the contained lubricating oil can be drained when I 
necessary, and in wood vessels an easily drained metal, or metal'l 
hned, tray must be fitted to prevent leakage of either fuel, oil, or j 
of lubricating oil from saturating the woodwork. 

7. Carburettors, where petrol is used, and vaporisers, whcrftl 
paraffin is used, should be so designed that when the engine IB l 
stopped the fuel supply is automaticAllyshut olf. If an overflow 
IB provided in the carburettor or vaporiser, a gauze-covered tray, 
with means of draining it. must be fitted to prevent the fael 
from Sowing into the bilges. 

Strong metallic gauze diaphragms should be fitted eitltei,1 
between the carburetter (or vaporiser) and cylinders, or at thfl J 
air inlets. 

8. If the ignition ia electric, either by magneto or by coil and^ 
accumulator, alt electric leads must be well insulated and snitably J 
protected from mechanical injury. The leads should be I 




MOTOR BOATS 263 

remote from petrol pipes, and should not be placed where they 
may be brought into contact with oil. 

The commutator must be enclosed ; and the sparking coils 
must not be placed where they can be exposed to explosive 
vapours. 

9. No exposed spark gap should be fitted. 

10. In paraffin and heavy oil engines, where lamps are used 
for ignition or for vaporising, these lamps should be fixed by some 
suitable bracket, and the flame enclosed when in use. 

11. The circulating pump sea suction is to have a cock or 
valve on the vessel's skin, placed on the turn of the bilge in an 
easily accessible position, and the circulating pipe is to be pro- 
vided with an efficient strainer inside the vessel. The discharge 
overboard is to be fitted with a cock or valve on the vessel's skin, 
if it is situated under or near the load-line of the vessel. 

12. The pumping arrangements are to be the same as would 
.be required in the case of a steam vessel of the same size and 
power, with the except i(m that no bilge injection need be fitted. 
In the cases of vessels fitted with water ballast, the water ballast 
pump must have one direct suction from the engine-room bilges 
in addition. 

In open launches, and in small sailing vessels in which the 
engines are auxiliary only, a suitable additional hand pump, 
fitted to draw from the engine-room bilges, may be accepted in 
lieu of a power-driven pump. 

13. The cylinders are to be tested by hydraulic pressure to 
twice the working pre>ssure to which they will be subjected. The 
water-jackets of the cylinders to 50 lbs. per sq. in., and the 
exhaust pipes and silencer to 100 lbs. per sq. in. 

14. The exiiaust pipes and silencer should be efficiently water 
cooled or lagged to prevent damage by heat, and if the exhaust is 
led overboard near the water-line, means must be arranged to 
prevent water from being syphoned back to the engine. 

15. The machinery must be tried under full working C(m- 
ditions, the report stating the approximate speed of vessel, the 
number of revohitions of the engines at full power, both ahead 
and astern, and the lowest number of revolutions of the engines 
which can be maintained for manoeuvring purposes. 

RULES FOR DETERMINING SIZES OF SHiVFTS. 

Section 3. — The crank, intermediate and other shafts, if of 
mild steel, are to be of not less diameters than as given in the 



264 



SHIPS BOATS 



followin;;^ table. When special steel is used, the sixes are to be 
submitted for consideration. 

1 . For petrol or parafiBn engines for sniooth-water services : 

Diameter of crank | 

shaft in inches i ~ ^^ ^'^ 

where D =: diameter of cylinder in inches. 
S =: stroke of piston in inches. 



Four-stpjke cycle. 


T»u-iii 


Lroke cycle. 


eachcrmnk. 


the bemrinss. 


For 1,2, 3 or 4 C vis. 


1 OI 


2 Cyls. 


c=a4 


C- -38 


»f ^ .. 




3 „ 


C = -36 


C = -40 


»» 8 »f 




4 „ 


C = -38 ! 


C = -426 


12 „ 




6 „ 


C = -44 


C = -49 



For open-sea service add '02 to C. 

Diameter of intermediate and j _ri^T)*>a/ "X o\ 
screw shafts in inches ( ~" V • / 

where D = diameter of cylinder in inches. 
S =stroke of piston in inches, 
n = number of cylinders. 



For smooth-water services. 


For open-sea seryices. 


C s '155 for intermediate shafts 

C 170 / ^^^ screw shafts fitted with continaous \ , 

\ liners / ' 
0=**180 } ^^^ screw shafts fitted with separate^ 

) liners or with no liners J 


C « 166 
C=180 

C=190 



In engines of two-stroke cycle, n is to be taken as twice the 
number of cylinders. 

2. When ordinary deep thrust collars are used, the diameter 
(){ the shaft between the collars is to be at least |(\ths of that 
of the intermediate shaft. 

3. The above rules apply only to engines in which the initial 
pressure does not exceed 250 lbs. per sq. in. In the cases of 
semi-Diesel and other engines in which higher initial pressures 
are employed, particulars should be submitted for special 
consideration. 



MOTOR BOATS 265 

FUEL TANKS AND CONNECTIONS. 

Section 4. — 1. Separate fuel tanks are to be tested with all 
fittings, to a head of at least 15 ft. of water. If pressure feed 
tanks are employed, they are to be tested to twice the working 
pressure which will come on them, but at least to a head of 15 ft. 
of water. If the tanks are made of iron or steel they should be 
galvanised. 

2. Strong and readily removable metallic gauze diaphragms 
should be fitted at all openings on petrol tanks. 

3. Paraffin or heavy oil tanks, not used under pressure, are 
to be fitted with air pipes leading above deck. Pressure-feed 
tanks and tanks containing petrol, should be provided with escape 
valves discharging into pipes leading to the atmosphere above 
deck. The upper ends of all air pipes are to be turned down, and 
pipes above 1 in. diameter are to be provided with gauze dia- 
phragms at the end. 

4. No glass gauges are to be fitted to fuel tanks containing 
either petrol, paraffin, or heavy oil. 

5. Filling pipes are to be carried through the deck so that 
the gas displaced from the tanks has free escape to the atmosphere. 

6. Separate fuel tanks should be provided with metal-lined 
trays to prevent any possible leakage from them flowing into the 
bilges, or saturating woodwork. Arrangements are to be pro- 
vided for emptying the tanks and draining the trays beneath 
them. For petrol tanks the trays must have drains leading 
overboard where possible, or they should be gauze-covered trays 
with means for draining them. 

7. All fuel pipes are to be annealed^ seamless copper with 
flexible bends. Their joints are to be conical, metal to metal. 
A cock or valve is to be fitted at each end of the pipe conveying 
the fuel from the tank to the carburettor or vaporiser. The fuel 
pipes should be led in positions where they are protected from 
mechanical injury, and can be exposed to view throughout their 
whole length. 

8. The engine-room, and the compartment in which the fuel 
tanks are situated, are to be efficiently ventilated. 

9. An approved fire-extinguishing apparatus must be supplied. 

PERIODICAL SURVEYS. 

Section 5. — 1. The machinery is to be submitted to survey 
annually. At these surveys the cylinders, pistons, connecting-rods, 



SHIPS' BOATS 

Vnak aiid other shafte, inlet aud exhaust valves and gear, 
«Jutches, reverfiing gear, propeller, sea counections, and pumpe, 
are to be examined. The electric ignition is to be examined 
(and the electric leads tested. The fuel tanks and all 
Connections are to be examined, and if deemed necessary- by the 
•urveyor, to be tested to the same presHure as required when new. 
If practicable, the engines should be tested under working 
conditions. 

2. The Hcrew shaft is to be drawn at intervals of not more 
, than two years. 

SECTION B.— NESTED BOATS 

General Desorlption. — By the terms of General Rule 12 of the 
Lifp-aaviug Appliances Rules (1914), additional lifeboats may be 
stowed in tiers of two or three one above another, or they may, 
subject U} such conditions as the Board of Trade may impose, 
be fitted one within another. 

Captain P. D. Murray, of Liverpool, has bad an extensive 
experience with the Mercantile Marine Service, having served 
in sailing aud steam vessels for 21 years at aea, and was marine 
superintendent of two Atlantic steamship companies [or another 
21 years. 

The ninkiui^ of the R.M.S. Titanic, as the result of a collision 
with an iceberg, prompted Captain Murray to endeavour to con- 
struct ordinary open lifeboats of Class I. of sufficient strength 
so as to " nest " one or more boats within another,* and thua 
provide accommodation for all persona on board the largest 
passenger vessels, which would include the crew in addition to 
the fuU number of passengers. 

Theae particular boats designed by Captain Murray form tlie 
subject of the present section. 

For classification purposes they are treated as Class 1a open 
lifeboats, but they differ from the ordinary Ufeboata in that the 
thwarts are movable, not portable, and made to hinge to one 

The boats are constructed of wood of the best materials and 
workmanship. 

Fig. 149 shows the general stowage of tliree of the«e patent 
boats in a nest. 

For the purpose of nesting, the thwarto of the two lower boat« 
are hinged to the side of the boat, and to secure the necessary 
strength for sustaining the upper boat, a fore and aft stringer is 



NESTED BOATS 2C7 

fitted around the inside of the boat on a hne with the tliwarts, 
strengthened by galvanised steel angle bars secured throiy^h the 
foie and aft stringer, planking, stem, and stempost. By fitting 
t^ree or more deep frames connecting from the deep keelson and 
extflodiog to the fore and aft etringers, the boat is well tied 
together both in a longitudinal and in a transverse direction. 
These web frames are strengthened by angle bars fitted in one 
piece, following the line of the upper edge of deep frames 
across the keelson, and secured to the fore and aft angles and 
keelson. 

A deep keebon is fitted in one continuous length, made from 
pitch pine and forms a good stiff backbone to support the weight 



¥m. 1411. -KiTtii.ii shtiwing st<)uiij?3 u( Ciijitjiiii -Mumiys nunted lifcb"nl«. 

of the upper buat. .A recess is provided for the keel of the upper 
boat to rest on the keelson, by forming fore ami aft scats, resting 
on the deep frairie-s. and extending the full leugth on both sides 
of the boat. Two additional fore an<l aft seats are fitted above 
the lower ones so that seating accommodation below the thwarts 
is provided for about half tlie number the boat is certified to 
carry, which ensures greater stability, and freedom for the 
rowers at the thwarts. 

The side stringers and thwai-ts provide seating accommodation 
for the remainder of tJie persons carried. 

The space betwet^n the fore and aft stringers and the lower 
edge of the side seats, around the sides of the boat, provide ample 
space for the rojuired volume of buoyancy air-cases, viz. : one 



268 



SHIPS' BOATS 



cubic foot for every ten cubic feet of boat capacity obtained bv 
Stirling's Rule. • . 

The air-cases are of special design, giving the greatest buoyancy 
at the bilge of the boat. 

Under the seats on each side of the keelson is provided stowage 
for water and biscuit tanks, and in a locker fitted aft are placed 
the Uquid compass, distress signals, etc. 



( t ■■ 

Mouse**- -^ "8>V^' 



/ 

\e LEG ATION or 

j MODiriED N OQH B 



- PLAN or SHACMLF 

rm. 



CHAIf\t 




SHACHl I 




- PLAN - 



OETAtL Of 






OA/f 







Fia. 150. — Details of lifting gear for nested lifeboat. 



The space between the seats in the bottom of the boat provide 
stowa<^e for oars, mast, sails, and full equipment. 

Foui- hinged thwarts are provided for oarsmen, double banked, 
and supplied with special fittings to permit of stowing the thwarts 
on edge on top of the fore and aft stringer, when the boats are 
nested. 

The general arrangement of a nest of lifeboats is shown in 
Fig. 151, wliich indicates the positions of the thwarts. 

As the upj)er boat is launched, the thwarts are placed across 
the second boat and secured on opposite sides by cleats, ready for 



NfeSTBD BOATS 




F¥^- 




^e use of the oarsmen. The boat is then in a condition for 
launching. 



270 



SHIPS' BOATS 



The Banie procedure is tAkea when preparing the t^iid i 
last boat. 

In a nest of three lifeboats, the lower two boata are con- I 
atnicted in accordance with the details described, but the top 1 
boat, havinj; fixed thwarts, is biiilt in exactly the same way as j 
an ordinary' pulling boat of Class Ia. and fitted with jfarrf lifting- I 
hooks. 

Slings are fitted for carrying the lifting-hook for attachment 
to the da^Ht blocks. They are well secured to the keelson and deep 1 
frame at each end of the boat. Connection is also made to an eye- j 
plate welt secured to the stem and stempost, as shown in Fig. 160. 1 
The hook ia steadied by guy chains secured to eye-bolts in the j 
fore and aft stringers, and attached by clip hooks on the oppoaito I 
aide to which the sling chain is secured to the keelson ; so that 7 
by unhooking this guy chain, the sling will drop clear of the top J 
of the keelson from its secured position. I 

When the upper boat is launched, it is only necessary to hook "I 
on this guy chain, adjiist the thwarts, and the second boat ia 
then ready for lifting. 

Nests may consist of two or three hfeboats. A nest of three! 
would consist of boat« of the following dimensions : — 

No. 1. 260' X 68' X 30' accommodating 35 persons 
No. 2. 280' X 8-2' x 36' „ 56 „ 

No. 3. 300' X 9-8' X 4-2' ,. 82 „ 

Total accommodation in one nest = 173 persons. Neets of ^ 
28 ft., 26 ft. and 24 ft. boats are provided, if desired, to suit the 
requirements of the deuk space on board. 

Nested boats can be placed under any davits, provided suffi- 
cient hoist b given for launching the two inner boats from the 
outer one, and allowing the keels to clear the gunwale of the boat 
that is sitting in the chocks. A drift of about 10 ft. is considered 



The photograph shown at Fig. 153 shows the adaptability of 
Messrs. Babcock and Wilcox's patent long-reach davits to suit 
the requirements of these nested boats. Boat chocks are only 
required for the lower boat, each nested boat having its keel resting 
on iha keelson of the lower boat. When the three boats are 
secured in their correct stowing positions, the total depth formed 
by the keels and keelsons amotmts to 3 ft. C> in., providing a 
girder which helps to distribute the weight and prevents deflecUon. 

Only one set of gripes is required, fitted in the usual manner 
to the lower boat with slip liiiku on each, and extensinn gripes a 



NESTED BOATS 



271 



carried up to the middle and upper boats, security being made by 
lanyards. Thus each boat is kept in its relative position, un- 
afiected by the rolUng of the ship, permitting the gripes o[ each 
boat to be detached in rotation as the boats are launched. 

In an emergency, by disconnectii^ the slip hnks to the lower 
boat, all three boate are free to float away. 

One canvas cover protects all three boats of the neat, and the 
spar, which is placed between the lower blocks of the davit to 
prevent the tackles from becoming " cable laid " and ffJuHiit; after 
launching the first or second boats when rounding.' up the falls. 




I 



Murray's oestod lifebo»tB. 

serves the purpose also of a ridge spar to take the canvas cover. 
The latter is laced in the usual manner under the rubbers of the 
lower boat. 

The system of neatint; Ufeboats has several advantages which 
appeal to some shipowners, the most important of which is that 
the boats are stowed imiaedjately under davit«, thus dispens- 
ing with the necessity of fitting transporting gear to bring boats 
stowed inboard to the ship's side. It is further contended that 
a conaidferable saving of time is effected. 

It may also be mentioned that Captain Murray lias made 
another improvement in the type of lifting-hogk fitted to the 
chain slings. .\ departure has been made &oni the plan shown 



272 • SHIPS' BOATS 

at "A " in Fig. 150, and a new arrangement subBtituted as at 
" B." When the tackle falls are slacked for the purpose of un- 
hooking the boat, the hook is kept fairly upright by the steadyinj^ 
chains. Aa the boat becomes water-borne the locking arrange- 
ment is relieved and operated by a Bmiill cord attached under 
the point of the hook when locked, and at the lowest point when 
open. The action of the horn on the hook prevents the link of 
suitable size on the tackle-block from moving in any direction but 
towards the point of the hook, and will thus cause detachment. 




Fid. 153.— Nested lileboatB under Biibcock 



The mousing arrangement prevents the falls from detaching 
themselves from the hook. 

A complete set of Captain Murray's patent nested boats is 
iUustrated in Fig. 152. The photograph was taken in the boat 
yard of Messrs. Qouk and Nesbit, Glasgow. 

Before this principle of constructing nested borfta was 
accepted by the Board of Trade, very detailed and extended 
testa were earned out in Liverpool, und«r service conditiona. 
It will serve no useful purpose to refer to these teste in any detail, 




SUKF BOATS 



273 



but briefly, they were: (1) Strength; (2) Stability; (3) Freeboard 
and Flooduif; ; (4) Laimchinj; ; (5) Seating; and Rowing. 

It is of intereiit t(i note that with reference to test No. 3, the 
buoyancy tanks were removed from the 3l"^ft. lifeboat, the plu>; 
waa removed and the boat filled with water. She remained in 
that condition for 21 hours, the freeboard rau^dnf; from H to 
5 in., dpnionatratinii that t!ie boat will more than support the 
steel anyles and ironwork used iu the constmction. 

No. 4 test only oc^cnpied l(i minutes, the three boats being 
laimchefl in that time from the deck of the R.M.S. VKtorian in 
the Canada Dock. Liverpool. 

It may also be of interest to mention that one boat of a neat 
on .1 liner, torpedoed some 230 miles off the Fastnet, was 
picked up two monthB later in good condition ofi the Clate Coast 
of Ireland. 

Donble-skin boats are aupplieil to vessels sailing to the tropica, 

where the single thickness will not stand the excessive heat 

and remain watertight. The double thickness will ensure a 

" tight "' boat, and is made with outside plaiikiny of oak and 

aide of larch, having a layer of oiled calico placed between the 

|j.8kins, 

SECTION C— SURF BOATS 

^il«n«tal Description. — Siu'f boats are constructed to meet the 

iquirements of vessels engaged in a particular trade. 

It is impossible for ordinary pulling boats to be utilised along 

bain parts of the West Coast of Africa, and a large portion of 

2ie cargo has to be transported from the shore to the vessel, which 

' ia a difficult and tedious operation. 

8ome shipping companies have specially constructed motor 
boats to facihtate the work of loading, but in certain parts these 
ue found to be inadequate to meet the circumstaucea of a shallow 
^ore and heavy aurf. 

Where vessels are trading in palm oil, the boata have to be so 

istructed to take a number of casks or jnmcheona. 

G}«netally speaking the surf boats are divided into two 

ifierent claases. The two-jmncheon boat, i.e. one which is 

iged internally to accommodate two caska of palm oil, are 

1 for beach work. They are canted over on one aide and the 

s are simply rolled in. There are no side benches, buoyancy 

C8, mast, nor sails. 

The thTee-(iHncheon bouts are arranged to take throe casks of 

Bpalni oil between the thwarts; they ar^iittod with the usual side 






benches, buovancv tanks, and lilting-liooks. These boats form a 
part of the vessel'a statu- 
te iry equipment, and are 
not engaf;ed in beach 
>v(irl(, but attached to 
ilie veMel. A featnre of 
the equipment of a 8urf 
beat is that they are 
propelled with jxid^iles, 
not oars. 

In view of the hazard- 
1.H1S nature of the work 
in which these boats are 
enjiaj^ed, partirular at- 
tention is paid to the 
structure, which is made 
stroni: enou<;h and formed 
in aiich a way as to 
iiinet the heavy pounding 
received from a shore 
8urf. 

A ^'Cneral idea of the 
aiTan;remeiit of midship 
section is obtained by re- 
fcroncc to Fig. 155' It 
will he seen, in the first 
|)lace. that the planking 
is much thicker than the 
iiiHlinary ship's boat, and 
is worked on the "carvel" 
method, to enable the 
: timbers to lie completely 
home to their work and 
i^ive the planking; the 
nmximum amount of sup-' 
port. 

The thickness is I in., 
except at the bilge, where 
it is 1 1 in. The width of 
the plankti varies from 
4! t() ill., with the gat- 
biiiird not exceeding 6| 

to| 



I 



These planks 



worked in one length from 



^ >. 



SURF BOATS 



275 



i avoided. The material is uuiially pitch 



Ptts being thui 
pical-dimensioned boat would be — 
26' 0' X 6' 10* X 2' lOi' 

The whole character of the aurf boat is difierent to the ordinary " 
pulling boat, and the relation between the length and breadtji 
has not the same value owing to the particular formation of the 
enda. The design, therefore, has to be treated on its own merits 
in order to meet the particular circumstances of the case. The 
dimensions, general formation of structure, and other qualities 

• have been based upon the experience gained in actual work. 
The boat is double-bowed, with great cut-up both forward and 
aft. If reference is made to Fig. 154, the reader will find illus- 



I 




Fio. 156. — Midship BtotioQ o£ surf boat. 



trated a completed surf boat, constructed by Messrs, Philip 
Winram and Son, of Liverpool. The firm has been good enough 
to allow the writer full opportunity to give detail scantlings of 
these particular boats. 

Messrs. Eider Dempster and Co., Ltd., have quite a number of 
Burf boats carried on their vessels trading eastward, and it may 
be remembered that when the a. a. Falaba was torpedoed by the 
enemy, the surf boats played no mean part in saving a large 
number of lives. 

It will be seen from the figure referred to, that the stem, keel, 
and sterapost, are in one piece, bent to shape, from gunwale to 
gunwale. The scantlmgs arc 2^ in. deep by SJ in. in breadth. 

The thwarts are of heavy scantliug, being 7 in. in width and 
3 iiL in thickness. Four thwarts are fitted in two-puncheon 
boats, and five in three-puncheon boats. Tie rods f in. in 
diameter are worked under the thwarts from plank to plank and 
well secured to the outside, to assist in binding the boat together. 



376 



SHIPS' BOATS 



The deadwoods aiul apruus are seciLTM] from material gtoi 
to ehapc and are in one piece, sided 4J in, and moulded ij to 5 in. J 

The keelson ia bent at each end to meet the deadwoods with J 
which it scarpLa, sided 4j in. and moulded 2J in. Timbers are J 
of exceptional sti'eDgth, fitted from gtinwale to gunwale, spaced I 
from 8 to 9 in. apart, 2J in. sided and IJ in. moulded. 

There is an upper stiake of oak or other suitable hardwood, I 
6 in. by 1 in. in thickness, and immediately below is fitted an! 
extra thick strake of American rock elm, termed the bend, which I 
is secured to every timber with bolts and clenched on rings. The i 
scantling is 3J in. by 2 in., and fitted in one length. 

Sister keelsons are fitted between the end thwarts which act 
as riders for the casks. Bilge pieces, risings, and stringers, are 
fitted in one piece and thoroughly secured to timbers and J 
planking. 

The knees are of the special clamp type, as iltustiated i 
Fig. 86. 

Between each pair of thwarts, cask riders, two in number, are 1 
fitted, made up of half-rpund iron bars. 

Cross chocks are fitted, as shown in Fig. 155, four in number, I 
on each side, with galvaikised iron half-round, IJ in. wide, turned 1 
over the gunwale inside and fastened below through the chock, ' 
with bolts clenched on rmgs. 

Iron breaathooks and stem straps are fitted and well aecuredl 
with bolts. 

A stem plate and skeg band are fitted fore and aft, and thaj 
usual keel plates, et«., in connection with the lifting arrangem 
are the same as those approved for ordinary pulling boats. 

Good stout ring bolts, f in, in diameter, are fitted on the outsidi 
to enable the boat to be hauled up on the beach, and two sim 
bolts fitted inside for use with the painter. 

The usual practice is to coat the inside with tar. 

The main consideration throughout the construction of t 
particular type of boat, is streng^. The arrangement of co 
binations, etc., necessitate good workmanship, and seasoned 
material is absolutely necessary. 

The building of surf boats is practically confined to tiie Livet 
pool district. 

Sheer is given greatly beyond the standard for a Class. 1 
lifeboat, and in conjunction with the amount of cut-up at t' 
stem, allows the boat to rise to the waves or surf, and keep t 
interior fairly dry. 

A typical specification indicating scantlings and material i 



SUKF BOATS 277 

inserted for information. There may be very slight differences 
in dimensions among the various boatbuilders, but the following 
will serve to give a general idea of the main considerations. 



THREE-PUNCHEON SURF BOAT. 

Dimensions : 26' 0^ x 6' 10" x 2' lOJ^ 

Keel. — American rock elm V x 2^^. Turned in one length 
from stem-head to sternpost-head. 

Deadwoods and Aprons. — EngUsh oak, in one piece, 5 in. sided, 
and moulded as required. 

Timbers. — -American rock elm, turned to shape 2J'' X 1 J"^, 
spaced 8 in. centres. 

Planking. — Pitch pine or red pine, 1 in. thick, from 4| in. 
to 5 in. width of plank, 13 strake^ each side. Garboard strake 
not to be wider than 6.J in. 

Bends. — ^American rock elm, 3|" X 2", in one length. 

Bilge Planks. — Pitch pine, 3 J" X IJ", in one length. 

Topstrake. — American elm, 1 in. thick, in one length. 

Gunwale. — American elm, 2| in. Square, in one length. 

Keelson. — American elm, 5" X 1|", to run well up to the dead- 
woods. 

Sister Keelsons. — Pitch pine, 3" X 3^, to nin between the end 
thwarts. 

Bilge Pieces. — Pitch pine, 3 J" X IJ^, in one length from 
dead wood to dead wood. 

Risings. — Pitch pine, V X V, in one length. 

Stringer. — Pitch pine, 3" x l^'', in one length. 

Thwarts. — Pitch pine, 7" X 3", and spaced to receive 3 
puncheons of oil. 

Knees. — 2 J in. iron cramp knees, forming iron rubbers outside, 
strongly and thoroughly through fastened. 

Breasthooks. — Iron, 2 J" X f. 

Bottom Boards. — Pine, 1 in. thick, secured to timbers. 

Stern-sheets. — Gratings fitted in accordance with plan. 

Cross Chocks. — Hardwood, 4 in number on each side, with 
galvanised half-round iron, 1^ in. wide, turned over the gimwale 
on the inside and fastened below through the chock with bolts 
clenched on rings. 

Ganghoards. — To be pitch pine of dimensions to suit the lifting 
hooks. 

Fastenings.- -T\\Q frame to be well bolted with galvanised 



278 SHIPS' BOATS 

iron bolts, and clenched on rings. The planking to be fastened 
with copper nails and well turned down on the timber, to the 
load-line. 

The bends to be bolted through every timber and clenched on 
rings. 

The bilge pieces to be bolted through every other timber and 
clenched on rings. 

The keelson and sister keelsons to be well bolted and clenched 
on rings. 

Ironvxyrk, etc, — Galvanised iron ringbolts, fitted inside and 
outside of boat, of sufficient strength to lift boat on end, and to 
be efficiently fastened. Stem, skeg, and keel plates to be well 
secured and galvanised. Bolts to be fitted imder the two 
midship thwarts, to have good heads and plates under same. 

Lifting-hooks to be fitted in accordance with approved plan 
of scantlings, and of sufficient strength to lift boat with the full 
complement of persons. 

Two chafing irons about 2 ft. 6 in. in length to be fitted at 
each side of boat. 

Brass socket and double plugs secured with chain. 

All iron work to be galvanised. 

The material used in the construction of these boats, as 
also the workmanship and finish, to be of the very best. 

The planking to be caulked and puttied. The inside of the 
boat to receive two coats of the best white-lead paint and three 
coats outside. 

Six half-round iron cask riders fitted between the thwarts. 

The inside of boat is usually coated with tar, in lieu of one 
joat of paint, which is matter to suit the requirements of the 
shipowner. 

SECTION D.— STEEL BOATS 

It is a remarkable feature in connection with the construction 
of lifeboats in the United States of America, where there is an 
abundance of suitable timber, that the metallic boat appears to 
find most favour. 

Several firms in Great Britain make a speciality of steel- 
constructed boats, but the demand is a very Umited one in com- 
parison with those built of wood. However, the arguments used 
by these firms, and by masters of vessels who have had experience 
with the metallic lifeboat, as to their general adoption under 
special circumstances, cannot be disregarded. 

The lelativo merits of lifeboats constnicted of steel compared 



STEEL BOATS 



279 



with those of wood, have very frequently been disciisged, and it 
is advocated by those persons who favour tlie former, that 
wooden Ufeboata carried on vessels passin;; through the tropics, 
are of little value when ct>nstrueted of woods such aa larch or 
wych elm, unless the plankint; is maintaini'd in a constant 
condition of moisture, which is undesirable, Tlie practice of 
filling boats with water up to about two feet below the gunwale 
should be discouraged, for the action of the water on the planic 
fastenings has the opposite effect to tliat which would be imposed 
on the boat when afloat. There should never be any necessity for 
this, and wooden boats should be constructed of such material as 
will obviate recourse to such a procedure. No objection could be 
raised to hoseing the outside planking during the early morning 
before the heat of the sun is great. 

With a steel boat the variation of the weather has little effect, if 
any, and remains in a condition for safe launching at the moment 
required. 

There is no doubt that where vessels are constantly trading 
on the seas and inland waters of the tropics, steel boats serve 
their purpose admirably, and their adoption can be recommended. 

An argument for consideration is that steel boata can some- 
'timea be launched from the deck of a steamer with a certain 
degree of safety, when a heavy sea is running, that would make 
the operation one of great danger to a wooden boat. 

The steel boat might become indented if brought into violent 
contact with the ship's side, but would remain in a condition of 
seawortliiness ; whereas the wooden lifeboat runs the risk of 
smashing the gunwale and planking during the process of lowering. 
There may not be much in this argument, because if there are any 
projections on the side plating of a vessel, the skin of the steel 
boat would probably be pierced, and a damaged steel boat is more 
difficult to temporarily repair than a wooden one. 

The argument of most value for the adoption of the metallic 
boat is in the case where the inboard lifeboats are in close prox- 
imity to the funnels. The influence of such great heat on any 
type of wooden boat in this position would have a damaging 
effect on the planking and render the lifeboat* unfit for service. 
The writer has noticed in the vessels of Messrs, Alfred Holt and 
Co., that invariably the owners and shipbuilders have considered 
this question in their arrangement of boat stowage. If reference 
ia made to Fig. 227 it will he seen that the outer boat stowed 
immediately under the davits is constructed of wood, while the 
one on the transporter, which has been moved from the inboard 



280 SHIPS' BOATS 

position and in close proximity to the funnels, is built of 
steel. 

In the case of fire on board a vessel, there would certainly be 
less risk of damage to the boats if they were constructed of 
steel. 

The object of this treatise is not to recommend one particular 
type of boat as possessing special qualifications for their general 
adoption on vessels, but to deal with the advantages and dis- 
advantages of each, and so enable precautions to be taken to 
avoid the difficulties. 

After a steel or metallic lifeboat has been in service for some 
time, the hull presents an uneven a'ppearance from the effect of 
coming into contact with the ship's side, or being dumped down 
with undue violence on the stowage chocks, and it may not be 
out of place to state that the crew of an ordinary cargo steamer 
are " no respecters of patent lifeboats." 

The main complaint raised against the general adoption of the 
metallic lifeboat, is the question of corrosion. From this point 
of view there is cause for anxiety, unless there is a frequent 
jieriodical inspection made of the interior of the boat every six 
months, or, at the very least, once in twelve months. 

The upkeep and oversight of all lifeboats, whatever the tjrpe 
may be, largely depends upon the energy and interest of the 
ship's officers, particularly the chief officer. If steel boats are 
left to themselves without the occasional surveys referred to, 
then the inevitable ro^sult is really no fault of the firm who 
constructed the boat, and cannot be used as an argument in 
detriment to the steel boat. 

Where corrosion is likelv to occur is in the vicinity of defective 

« ft.* 

galvanising, or where the surface has become chipped during the 
process of riveting. 

The buoyancy air-cases sliould be removed at each survey, 
and a careful inspection made for any signs of corrosion, particu- 
larly in way of the rivets, all woodwork, at the keel seam, and 
encls of boat, at the ends of thwaii^s, and especially behind the 
metal buoyancy tanks ; also in way of the welds where the skin 
is constructed on this method. 

In dealing witli })oats which have been in service for a consider- 
able period, it will usually be found that if any wastage of material 
has occurred, this is situated along the bilge, and particularly 
in way of the supporting chocks. In this connection it is essential 
for a (louhliug-plate to be always riveted to that portion of the 
shell which lests on the chocks, and fuiiher precaution could be 



STEEL BOATS 



281 



taken with advantage to the boat, by fitting sheet iron or canvas 
well soaked in white lead paint, on the upper surface of the 
wooden stowage chocks. 

The shell plating is galvanised inside and out, but there is 
always the diflBculty of securing a proper protective coating to 
the heads of the rivets, although they are tinned. Yellow metal 
or composite rivets are not admissible, owing to the effect of 
galvanic action which would be created between the two metals. 
Special precautions have to be taken to avoid this difficulty when 
metal buoyancy tanks are fitted. 

Messrs. Mechan and Sons, Ltd., of Scotstoun Iron Works, 
Glasgow, have for many years specialised in the ccmstruction of 







- FLUSH BUTT — 



^ 




EMBOSSSO 



^ 



- LAPPED BUTT - 




Fia. 15(). 



Fio. 167. 



Fawkes' patent embossed framing. (Pat. No. 22732-1910.) 

steel boat«. This firm also build the " Lundin " })ontoon lifeboat 
referred to in Section P] of Part IV. 

The Hfeboats of C-lasses Lv and IIL are constructed of steel 
plates rolled on the Siemen's-Martin open-hearth acid process. 
The plates are blocked to the required shape and planished to a 
smooth surface. The frames are formed on special lines, known 
as the " Fawkes' patent embossed framing," which obviates the 
necessity of fitting special timbers. The method is illustrated 
in Figs. 15G and 157, the spacing between the embossed frames 
being about 2 ft. Tlie laps, or ends of the plates, are embossed 
and connected to one another by steel rivets tinned on the 
outside. Fig. 150 (up{)er) shows the steel plates joggled so as 
to preserve a flush surface on the outside, which is of great 
advantage to a motor boat. Fig. 156 (lower) shows the skin 
plating worked with an ordinary lap. In both cases the interior 
of the embossexl frames are well coated with protective paint 
and filled with plastic cement. 



282 SHIPS' BOATS 

The steel plates are blocked to the correct shape, embossed 
in a special rolling machine, all the work completed except the 
actual riveting, and then galvanised in the firm's own baths by 
the special hot process. The plates are then erected and the hull 
is double riveted with tinned steel rivets. 

The sp^ms of the Ught plated hulls are made watertight by 
inserting special tape dipped in red lead, but the heavier hulls are 
caulked. 

Boats which are constnicted in sections on the principle 
referred t^) are very suitable for transporting abroad for use on 
inland waters. 

In a double-bowed boat, the stem, stempost, and keel are in 
one length, bont to shape, and consist of a rolled bar of section 
shown in Fig. 157, the shell plating being single riveted to this bar. 




e^forcft 



ar££L 



/f£ iff^e 



SECTION ELEVATION 

Fi(3. 158. — Method of securing crutches and li{e-lino^«*. 

The thwarts, side seats, etc., are usually formed of teak or 
yellow pine, of scantlings equal to wooden lifeboats. It is 
essential to keep all woodwork in a metallic boat from having 
direct contact with the hull, but where the gunwale, upper strake, 
and rubber are of wood, direct attachment to the steel hull cannot 
be avoided. In some boats, Mechan's patent embossed steel 
gunwale is adopted, which is a combination of gunwale, upper 
strake, and rubber. Fig. 161 illustrates the arrangement in 
section. An alternative scheme for fitting a steel gunwale 
which consists of a bulb angle, is shown in Fig. 158. 

The thwart knees and breasthooks are made of steel on the 
ombossod principle, riveted to the liull plating and bolted to the 
thwarts. (See Fig. 159.) 

Life-line rings are secured to tlie hull just below the rubber or 
bulb of tlie gunwale by rivet/ed cleats, spaced 18 in. apart as 
shown in Yvx. 158. 



STEEL BOATS 283 

Watertight air-cases are fitted in steel boats, but an addition 




SECTION ELEVATION 

Fio. 159. — Method of secnrjng thwnrts to aides. 




li 



fT 



E5 





SHeil. ^LKTMt 



ELEVATION SECTION 

FlO. 160.— Details of lifting-hook for stwl lifeboat. 



is made to the cubic capacity so as to give the steelboat buoyancy 
equal to that of a wooden boat. 



284 SHIPS' BOATS 

The method of obtaining the correct volume of metal air-cases 
is dealt with in Section C, Part VI. 

Particular care should be given to the arrangements made for 
the removal of the air-cases to faciUtate easy access when the 
periodical inspections are made to ascertain the condition of 
the hull. 

The tanks must be kept from contact with the steel shell, 
a simple arrangement being the fitting of two lengths of rope 
round the tanks to act as a fender. 

The lifting-hooks are formed at the head in similar fashion 
to those approved for wooden lifeboats, and the scantlings are 
identically the same, as there is very little difference in the weights 
of the steel boats as compared with those of wood. There is a 
difference to the keel plate fittings, owing to the formation of 
the keel. The method of securing the lifting-hook to the hull 
is shown in Fig. 160. 

The whole of the inside and outside of the boat is coated with 
two good coats of oil-paint. 

TYPICAL SPECIFICATION FOR GALVANISED STEEL 

LIFEBOAT. 

Dimensions : 28' O'' X 8' 6'' X 3' 6'' = 50 persons. 

Shell Plating. — Siemens-Martin mild steel sheets, 14 B.W.G., 
built on Fawkes' patent embossed steel framing principle, flush 
plated and flush riveted on outside. Doubling plates in way of 
chocks. Frames filled with plastic bitumastic composition. 

Galvanimig . — All steel plates galvanised by the hot process 
after working to shape and punched. 

• Keel, Stem, and PosL—Oi bulb tee, 5'' X 1 1'' X IT X T- 
Section of specially rolled steel bar. 

Gunwale. — Of specially rolled bulb angle section. 

Thwarts.— Oi pitch pine, 8x12''. 

Side Be^iches. — Of pitch pine, 1 in. thick, continuous over 
thwarts. 

Rudder and Tiller. — Rudder of English elm and tiller of ash 
or elm. 

Buoyancy Tanks. — C'Onstructed of yellow metal of 21 ozs. 
per sq. ft. To be securely held in place. Rope strops wound 
roimd tanks to prevent injury by contact with shell. 

Mou7i(i7ujs. — Galvanised steel thwarts supports, embossed 
kneas, mast step, mast hasp, cleats, 1| set galvanised steel 
rowlocks, double banked at all thwarts, and steering rowlock 




STEEL BOATS 

tltteii, all attacheiL with galvanised chain. Galvanised shackles 
at ends. 

Lifting-Hooks. — ^To be fitted as per special plan. 

Gear Box. — Pine box for stowing details of outfit supplied 
and fitted. 

The Seamless Steel Boat Co,, Ltd., of Wakefield, 13 another 
well-known firm who have specialised in a particular type of 
construction, both for ships' boats and motor boats. They have 
their own patent method of formin>; the ahoU plating. 

The hull is made of sheets of Siemens-Martin mild steel, 
pressed into the requii-ed shape, welded together at the butts, 
and riveted to a steel keel bar of the bulb section, which fonns the 
stem, keel, and sterapost. The whole of the shell plating and steel 
work attached, is thoroughly galvanised. 

The inside of the hull is covered with two coats of bitumastic 
solution, and the outside with two coats of the best white-lead 
paint. 

The top atrake is of teak, gunwale of j^ierican elm (or formed 
of special moulded steel), rubbers uf American elm, thwarts, side 
aeate, and deck ends, of yellow or red pine. 

Canvas soaked with white lead paint is fitted between the 
plating and keel, stem, and stempoat. 

Wood timbers arc sometimes fitted, and sprung into position 
from keel to gimwale, secured in such a way that they can be 
removed for painting. 

A plan which has found favour with the firm is to fit a lijjht 
steel angle, riveted to the bar keel, and guuwale, so as to be 
easily removed, with a piece of elm fixed to the bosom of the bar 
to hold the tanks off the sharp edge of the bar. The idea of the 
angle is not to atiilen the boat, but merely to hold the tanks away 
from the hull. 

Mr. James ,\nder8on, in a paper read before the Listitute of 
Engineers and Shipbuilders in Scotland, on the 23rd of November, 
1915, referred to a new method of forming steel plates for the 
construction of steel boats, a system which has already been in 
operation in some of the American yards. The boat appears to 
be constructed of a number of longitudinal strakes of steel 
plating, sliaped in similar form to the planks of an ordinary 
chnket-built wooden boat, but the landing edges are secured 
together by means of a double^hook joint, aa shown in Fig. 162, 
The joints are closed and made watertight with hammers or 
roUeis. 



286 



SHIPS' BOATS 



The plating is attached to a V-shaped steel stem, stempost, 
and keel. Wood timbers are attached to the shell by means of 
small lugs, which are closed in with the shell plating. These 
lugs have two sides in which the timbers lie, and are secured 
with through fastenings placed in a fore-and-aft direction. Bj 
this method it is advocated that no fastenings in the hull will be 
subjected to corrosion. 

An inside and outside gunwale is secured to the plating and 
timbers. 

The interior of the boat is thickly coated with bitumastic 
solution. 

The Uriited States Board of Supervising Inspectors have 



STffAHC 



B£'IT 



SH£ll 




DOUBLE HOOK 
^ JOtNT 



CAfSOSSeO 




Fig. 161. — Mochan's patent embossed Fig. 162. — Hooked joints for 
steel gunwale. (Pat. No. 8852- steel shell plates of lifo- 

1911.) boat. 



issued standard regulations governing the construction of all 
metallic lifeboats for ocean-going steamers. 

The keels, stems, stemposts, gimwales, and nosings, may be 
of clear grain, sound oak, or other suitable wood, each in one 
length, except that the gunwale and nosings may be made in two 
lengths. When made lq two lengths, the gunwales must be 
scarphed with a good long bevel scarph, stiffened on the underside 
by a piece of gimwale material, at least 2 ft. in length, \\ in. thick, 
and the width of the gunwale. 

The stem to be of natural or steamed crook, scarphed at least 
9 in. in length on the keel, and fastened thereto with two f in. 
through clinch bolts driven through the deadwood. 




STEEL BOATS 



287 ^1 



The sternpost to be stepped over the end of the keel, lialf 
the length of the stempost, and recessed at least 2J in. deep into 
the keel, the whole to be secured on the inside by a crook or knee 
of sufficient width to receive the flanges of the shell plates. 

Each joint of the stem and stempost ia fitted with two | in. 
atop waters, under the shell flanges. Bearding of stem and 
stempost is not to be leas than 1| in. 

The flanges of the shell plates on boats not over 20 ft. in length, 
to lap on the keel, stem, and stempost, at least 2} in. ; in boats 
over 20 ft., and not over 24 ft. in length, at least 2^ in. ; and in 
boats over 24 ft. long, at least 2J in., to be fairly drawn up and 
nailed over a strip of No. 6 cotton duck, the width of the flange, 
and secured by three rows of galvanised naila driven zigzag 
fashion. 

No part of the keel, stem, or stempost, outside of the shell 
flanges to be covered with sheet steel. 

The following particulars give the approved limiting gauge 
of shell plates, viz. : — 

Length of boat. Gauge 

Up to and including 20 ft 18 B.W.G. 

Over 20 ft. and not over 24 ft 16 B.W.G. 

Over 24 ft 14 B.W.G. 

All the .seams and Joints ate double rivet«d. The aeains 
and butt laps are not less than Ij in. The centre of the 
*■ of rivets nearest the .edge of a ^eet are about | in. from 
the edge. Rivets are staggered with not less than 18 rivets to 
the foot, having countersunk heads. The diameter of shank of 
rivet is not less than No, 10 B.W.G. 

The width or siding of wood keels, stems, and stemposts, vary 
from 1-8 in. for an 18-ft, boat to 2'8 in. for a 28-ft. boat, while the 
depth or moulding variea from 4'2 to 50 in. respectively. 

Steel having one-sixth of the approved sectional area of wood, 
may be used in lieu of wood fur keels, stems, stemposts, and 
gunwales, of metallic lifeboats, 

The keels of all boats over 26 ft. in length are strengthened 
by the addition of a main keelson extending not more than two- 
thiids the length of the boat, and having one-half the area of the 
main keel, to which it is through fastened wtth | in. clinch bolts 
spaced not less than 14 in. 

The sizes of wood gunwales vary from Ij in. in depth by[2 in. 
in width for an 18-ft. boat to 2| in. by 2| in. for a 30-ft, boat. 



L 



288 SHIPS' BOATS 

TJie giinwalea are attaclied to the thwarts by steel braces and 
teed to the thwarte, and secured thereto, and also to the steel 
plating by bolts, the aecuring bolta to plating being clinched on 
the outside. 

The sheer strake is brought to within a J in. of the top of the 
gunwale, nailed thereto by IJ in. boat nails, spaced 6 in, apart. 

Thwarts are made of clear yellow pine or fir, and are of the 
following scantLn^s, nz : — 

Length i>[ bust, Souitling. 

20 ft. and under 7i' X IJ' ' 

21 ft. to 24 ft 8' X li' 

Over 24 ft 9' X li 

All thwarts over Ij ft. lon^ are supported by stanchions of 
pine 1 in. by 5 in. Every thwart is aecuri3d at each end to the 
boat side bv a double or u flange of No, Iti plate, riveted to the 
shell with five rivets, the thwarts being fitted between the flanges 
and secured thereto by five boat nails driven down through the 
upper flanges, tliwarte, and lower flanges, and turned over 
beneath. 

Midship footings are fitted to the inside of the bull over a coat 
of lead paint, and held in place by straps of No. 18 plate 1^ in. 
wide. The midship footings in boats over 18 ft. and not over 
24 ft. long, are not less than 1 in. thick by 12 in, wide, and have 
three footings on each side, 1 in. thick by 7, 6, and 4 in. respec- 
tively in width. Boats over 26 ft. in length, ha\Hrig a keelson, 
are fitted with three footings on each side, 1 in. thick by 8 in., 6 in., 
and 5 in. respectively in width. The securing straps pass up 
through an aperture in the middle of each footing and receive a 
toggle of gas pipe, f in, in diameter, and of a length not less than 
two-thirds of the width of the footing. The number of toggles 
fitted in each footing varies from four to six. 

Breasthooks are formed of steel, varying in size from i in. 
thick by IJ in. in width, to f\ in. by 1 j in. No breasthooks are 
leas than 9 in. long, and are fastened through the gmiwale on each 
side, with three { in. button-headed bolta clinched over the shell 
plating. 

Rudders are made of clean, straight^grained oak, or fir, stiffened 
across the bottom edge by a piece of wood of the same character, 
properly nailed. 

Each hfeboat is fitted with an automatic plug. (See Fig. 112.) 



PART VI 

SECTION A.— DETAILS OF LIFTING HOOKS, KEEL 

PLATES, CHAIN SLINGS, ETC. 

Lifting Hooks. — The fitting of suitable lifting hooks in a 
lifeboat is of the greatest importance. Provision is made to 
meet the ordinary conditions of lowering a boat over the side of a 
vessel into the water, with a disciplined crew, and, in addition, 
the " unusual " or " extraordinary " circumstance has to be 
well considered. The passengers may be in a condition of 
nervous excitement or panic during the operation of lowering, 
with a heavy sea running, and the work of launching the boat 
may be undertaken with the help of untrained persons. In such 
circumstances, stresses may be exerted on the Ufting hooks which 
under ordinary conditions would not be anticipated. 

Therefore, in the first place, the lifting hooks and their attach- 
ments must be designed so as to be strong enough to carry the 
weight of the boat, full equipment, the total number of persona 
appropriated to the boat, and having in reserve a, factor of safety. 
This factor of safety is the only feature which is open to argument 
or criticism, as its magnitude is intended to cover all requirements 
and the ^* unusual ' circumstance. 

Little attention at one time was paid to this important question 
when fitting out lifeboats intended for cargo vessels, and until 
within a matter of three or four years ago it was quite the common 
practice to insert welded lifting hooks having shanks which were 
driven through the keelson and keel, and simply clenched over a 
small plate about J in. in thickness. The weight of some three or 
four tons was therefore hanging in mid-air, which depended entirely 
on the efficiency of a very doubtful clench. To say that the same 
principle was commonly carried out in the case of lifeboats for 
pas.seni!;er vessels would be an exaggerated statement, but, 
iievorthelo.ss, the (juality of the lifting hook connections ^as often 
open to .serious doubt. 

Recent regulations issued by the Board of Trade, it is hoped; 

u 



290 SHIPS' BOATS 

will prevent the difficulties, to which reference has been made, 
occuning in the future. 

" Safety first " is a warning which has riveted itself on the 
minds of many people in Great Britian, through their intimate 
contact with the posters displayed on the municipal cars, and 
it is one that is well advertised throughout the United States 
of America, and should be made applicable to all the various 
considerations associated with the life-saving appliances on board 
a merchant vessel. 

The present-day type of lifting hook may look heavy in 
appearance as compared with hooks used for other purposes 
in the shipyard, and particularly with those fitted in lifeboats 
previous to the issue of definite regulations, but in dealing with 
ships' lifeboats, there should be no doubt on the question of 
strength, and every opportunity taken to avoid error or the 
slightest appearance of weakness, especially when discussing 
the suitabiUty of lifting hooks. 

Before further investigation, the instructions issued by the 
Board of Trade in July, 1916, should be considered. Recent 
experience has added much to these requirements, but they still 
form the basis of the regulations, and are as follows : — 

" All sUng hooks fitted in open boats should be of the^erf type, 
unless, on the special application of the owners, some other 
approved type of hook is adopted. All hooks must be of ample 
strength having regard to the load carried, and should be of 
wrought iron or steel. Welded hooks should be of wrought iron. 

" The proportions of all parts taking the weight of the boat 
should be such as to provide a factor of safety not less than four, 
and the arrangement should be strong enough to carry the boat, 
equipment, and full load of persons with that factor. 

" Unless the bolt and fittings are tested as described below, 
the material is to be assumed to have an ultimate strength in 
tension not exceeding 18 tons per square inch. 

" If a higher tensile strength is claimed for the material, 
or if the surveyor is not satisfied that the strength is sufficient, 
the lifting hook, together with the sling bolt and fittings for 
attachment to the boat, is to be subjected to a proof test of at 
least the total weight of boat, equipment and persons. (Modified 
by recent instnictions, see Scantlings of Lifting Hooks.) A 
sample should also be tested to destruction to determine the 
approximate factor of safety. 

'' In welded parts, tlie calculated tensile stress is not to exceed 
three tons per s(|uare inch with the dead working load. 



LIFTINa HOOKS, ETH. 



291 



" Slinjr honks depending for their security upon a cleuflut! 
head alone, are not to be passed in new boats in future. In all 
lifeboats exceeding. 24 ft, in length, the sling hooks should be 
secured to eye-plates or to clamps of wrought iron or steel iitt«d 
on the top of the keelaon, and fastened to it by iron or steel screw 
boltw nutted on the inside of the boat, and the holts upset. The 
heads of the bolts should be ffirged with ample bearing surfaces, 
and should bear on a substantial plate fit.ti?d on, but not let into, 
the underside of the keel. 

" Any other method equally 8atisfacti>rj' may, however, be 
adopted. WTien the lifting huoks are required to be so near the 
ends of the boat that they cannot be directly connected to the 
keelson and keel, special etreugthening arrangements should be 
fitted to prevent the boat being strained when it is lifted. Means 
should be provided for preventing the hook bolts from turning." 

Before we can succeasfully determine the correct sizes of 
lifting hooks, to enable them to withstand the effect of a certain 
definite dead load, it is essential that sufficient and accurate 
data should be at our disposal upon which to base the scantlings, 
We need to go beyond the investigations of theoretical calculatiorLa 
and secure this data from the results of actual tests. 

At the request of the writer, Messrs. Scott's Shipbuilding and 
Engineering Co., Ltd., Greenock, very kindly carried out a scries 
of extended testa on various sizes of lifting hooka, connecte<l to 
different; types of keel plates. The firm went to a great deal of 
trouble to secure sufficient information upon which to base a 
full scheme of scantlings for sizes of lifting hooks that would be 
strong enough for the purpose required. 

The boats were classified into lengths ranging from 15 to 30 ft. 
With each length were associated dimensions considered to be 
of maximum proportions. Upon these dimensions the maximum 
dead load coming upon the lifting hooks was obtained, which 
included the weight of the boat, equipment and full complement 
of persons. As an example, take an open lifeboat of Class I. of 
the following dimensions, which is not to standard size, but 
considered as extreme or of limiting proportions, viz. : length 
26 ft., breadth 85 ft., and depth 3-5 ft. The total load carried by 
the lifting hooks would be 5'4 tons ; each hook would therefore 
have to siistain 2-7 tons under working conditions. In other 
words, certain maxJniuin loads were allotted to each particular 
length of boat, and the sizes of the books were appropriated in 
accordance with these loads. 

From the results of these tests the sizes of lifting hooks and 



292 SHIPS' BOATS 

keel plates, given in Table XIX., were based. The factor of 
safety was three on the elastic limit. 

With riveted joints and other combinations it is somewhat 
difficult to obtain the elastic limit during the process of testing, 
and it is usual for the factor of safety to be based on the ultimate 
breaking strength, which is known as the nominal factor of safety. 

XT . 1 TT, r n e , Breaking Stress 

Nommal Factor of Safety = ^^^ — , . o, — 

-^ Working Stress 

When we come to solid drawn lifting hooks made from cable 
iron, where the difficulty of obtaining the elastic limit is not so 
greats it is very evident that immediately this point is passed, 
alteration to form and permanent set take place. If the load 
which produced permanent set, or the stress which came upon 
the material at the elastic limit, was not increased, but allowed to 
continue for a sufficient length of time, the hook would eventually 
straighten out so that the actual strength of the bolt is the elastic 
limit or yield point, and the ratio between this and a working 
stress is termed the true factor of safety. 

m T7 X £ C3 £ J. Stress at elastic limit 
True Factor of Safety = — ..^ , . 

Working Stress 

From the point of view of obtaining data for the purpose of 
formulating a scale of sizes for lifting hooks, testing material to 
destruction after once the elastic limit has been reached does not 
provide us with much useful information, beyond giving us the 
additional load which is required to break the hook, or produce 
fracture within a reasonable length of time. 

The difEerence between the stress which discovers the elastic 
limit and that which produces fracture, is the reserve strength 
of the hook beyond the elastic limit. 

No useful purpose will be served by the insertion of any details 
of the tests referred to, these were very carefully carried out with 
small increasing loads to ascertain the elastic limit of each indi- 
vidual hook, and the deflections were measured and tabulated. 

Considerable amount of work is put on the largest type of 
hooks in forming them into the required shape, the effect of which 
was made evident at the test. The material at " A," Fig. 163, 
immediatolv in way of the critical section, was under a very acute 
stress duo to the bending moment, and consequently became 
fat i.i«[ued. When a certain load was reached it produced a fracture 
to a depth of about half an inch, the load was increased, and after 
the hook was fully broken the fatigued portion at '* A " was found 



LIFTING HOOKS, ETC. 



293 






FiQ. 163 



FiQ. 104. 



FiQ. 105 






COMPARATIVE 
SECTION 










-ELEVATION — 



Sfcr/o/^CD' 




S£CrfOf¥£.r 




FlQ. IGtt. 



Fio. 107. 



294 SHIPS' BOATS 

to be fTv.stalli.sed, but beyond this depth the material showed 
gfKKl fibre. The load whicli produced the initial fracture exceeded 
the elastic limit. 

The full thickness of the material in lifting hooks of standard 
circular section, is maintained from the upper part of the shank 
in way of the ganc;board to just beyond the critical section ; from 
this position to the point of the hook the material gradually 
tapers to facilitate easy insertion for the link on the block 
attached to the davit falb. 

Particular attention should be paid to the distance between the 
point of the hook and the gangboard. WTien ordering the lifting 
hooks from the smith it is necessary to give him the distance 
between the centre of pin in the keel plat€ to the top of the 
gangboard. 

The particulars of iron lifting hooks in Table XIX. have been 
standardised tf> obviate the necessity of carrying out tensile 
tests in every case. The material is best cable iron. Periodical 
tests should be made from samples of the material used. Each 
hook is drawn out of the solid. 

A reduction is made in the scantlings when hooks are made of 
mild steel, but they are subjected to a proof test equal to one arid a 
quarter times the total weight of boat, including the equipment 
and the full complement of persons. Each hook must be 
stamped with the test load. 

No part of any lifting hook, whether of iron or steel, should 
be welded unless approval has been obtained from the Board of 
Trade, and approval is only given when each hook is subjected to 
a proof test with an increase in the factor of safety. 

The writer is fully aware of the expression of opinion among 
boatbuilders and shipbuilders as to the size of lifting hooks, 
which is considered excessive, but from the results of repeated 
tests, no reduction in the scantlings can reasonably be made 
unlass the factor of safety is lowered. 

All lifting hooks must be carefully annealed after forging, to 
correct the difficulty already referred to, which is produced by the 
amount of work put on the head of the hook while being forged. 

A common practice was to forge the actual hook separately, 
and weld it to a tapered shank as shown in Fig. 1G4. 

Another method was to weld the hook at the critical section, 
as shown in Fi^r. IGo, and usually with another weld in the shank. 
The lu^ad was loft flat to facilitate driving the bolt through the 
k(M»l and kc^elson. Each of the methods referred to depend on 
the onicioncy of a weld, and thus, particularly when 95 per cent, of 



LIFTING HOOKS, ETC. 



295 




mfTAstosctfew 

BOLT 




PLAN af^O£CMPlArC mf^-Af M£ei SHS^ 




or TY^es Saho Cap€ tntrm? 




Fia. 108.— Method of securing lifting hook at gangboard, and method of fitting keel plate 

when boat is lifted from the ends. 



SHIPS' BOATS 



TABLE 

Scaij: op Sizf^ fob Liftihg Hookb asd Ebei. 

To be trad in conjunction tcilh Fig. 168 (liftinQ 



Length □( boat in feet 



S0&.29. 



26 A 27. 



2C&25. 



Maximum dimenBionfl and dead i amv m .n ' ., _ .. .. 

h^. i,„-U.lir,g...ight of boat. ™*J.5t„« 28-0' x?;0'x 8-75. 20-O'x8-5- 

no. of KfsSDS a„d *quipinenl . [ T 9 tons. GB tons. 5-4 to, 

Ttpb of beel connection . 

Material 



Thickness of kod plate 
Size of Rocuring pin . . 
No. ol securing bolt'; . 
Size of securing l.olts. . 













Tj|,»A.- 


Type "A.' 


Tspe"A." 


Iron. 1 Steel 


Iron. Steel. Iron. | Steel. 


!J" i HI" 


»!•■ Ill 


• j i;~ 


m" 


2" 


,.. 


Ij" 1} 


• j li" 


15" 


,j. 1 1... 


li- If 


■|ir 1." 


3,„ ,,„ 


2J" 2J 


- 1 2!" 1 »i" 


2" 2" 


ir 1! 


- , li- 1 ,,.. 


or 1 or 


0" ■ G 


• 1 5)- sj- 


10" i 10" 


9i- «. 


' j 8-1 9" 


11" !■" 


IS" . 1! 


• f 11- , u- 




31" SI 


■ 1 3- , 3- 


li" 1 11- 


S" 1 < 


3" ; r 


11" 


li" 


V 


3 


3 


3 


{ It 


i:: 


3 (if f 


2(« 


I-- 



Mi/c— Lifting hooks to be of best cable it 



LIFTING HOOKS, ETC 



297 



XIX 

Plates fob Open Boats op Classes I. and III. 
hooks) Fi^s. 1G8, 1G9 arul 170 {heelplates). 



24 & 


28. 

>x30'. 
ns. 


22 & 21. 

220'x7-2.Vx2-75'. 
30 tons. 

Typo " B." 


20A 

200' X G' 
2-4 t 

Type 
Iron. 


; 19. 


18 & 17. 

1 


IGiS 

IGO'xS' 
1-6 t 

Type 
Iron. 


:15. 


240'x7-i 
3-9 to 


r5' X 2G'. 
ons. 


180'xG-26'x2-6'. 
i 1*9 tons. 

Type " C." 

Iron. 1 Steel. 

1 


75' X 2-8'. 

ODS. 


Type " 

1 


B." 

Steel. 


Steel. 


" C." 


Iron. 


Iron. 

ij" 

111" 


Stocl. 


steel. 


1 


10" 


Vi" 


12" 
11" 


ir 


lA" 


1 5i" 


1 

li" 

li" 
ij" 


ir 


12" 




n" 


ir 


1 

li" i 


1 "J " 

■^16 


li" 


H" 


li" 

2" 
1>" 


H" 


ir 


1 » " 


1" 


2J" 


lA" 


ir 


ir." 


If 


ir' 


If 


IS" 


15" 


!■'" 


1.1" 


li" 


IJ" 


li" 


ij" 

4J" 


li" 


IJ" 


, ^r 


"^i" 

^ 


■«•;" 

1" 


4^" 


4}" 


41" 


41" 


4i" 


8}/' 


H.V' ' 

1 


8" 


,71" 


7r' 


7" 


7" 


G>" 


6.J" 


H" 


i 


1" 


r' 


I" 

H 

1 


S'i" 


4 


i" 


r 




r 


:>'■ 
1 


— 


\ 


— 




1 
1 


— ' 1 

1 


— 


r 


A" 







2 



2((/ :♦" 



2 



2 (./ I:" 



\ Sec Table XX. (p. 301) for scale of sizes of Type'* C " 

keel plates. 



mild steel, and without welds. Keel plates of mild steel. 



298 SHIPS' BOATS 

the hooks were never tested, either practice possessed very little 
value. 

Wrought iron lends itself better for welding than mild steel, 
and welding the shanks of steel hooks should never be allowed. 
The quality of the weld depends on the workmanship, and the 
writer must confess that as the outcome of many tests to 
destruction and proof tests, failure at the weld is quite unusual. 
There is always present the element of doubt. The lifting hooks 
are of such importance and have to be subjected at times to 
sudden and unequal stresses, that the question should not be 
trifled with ; good workmanship coupled with suitable scantlings 
are, therefore, very essential. 

An interesting comparative test was carried out by Messrs. 
Church and Turner, smiths, of Greenock, in conjunction with the 
writer. 

Wrought-iron lifting hooks of circular section were made for 
a 28-ft. lifeboat of Class Ia, the scantlings of which agreed with 
those in Table XIX. 

Another hook was forged from the same material, and 
its section was worked out graphically to approximate to the 
correct theoretical pear shape. The area of the circular section, 
and that of the pear shaped, were checked by the planimeter, 
and the two made to agree, so that the sectional area of the two 
sections were identical. The comparison is seen in Fig. 166. 

The results of the tests proved to be very interesting but at 
the same time confusing. 

The elastic limit of the circular hook was greater than the 
pear-shaped section, but the ultimate breaking stress was greater 
in the latter than the former. The real strength of the hook was 
shown in the extent of the elastic limit. One would naturally 
expect the section shaped to suit the theoretical considerations, 
would give the better result, but this may be explained by the 
fact that unless the material at the flattened out portion of the 
hook is maintained in a perfectly true axial plane in a line with 
the pull, there is a twisting moment which is detrimental to its 
efficiency. All derrick and crane hooks are shaped on the 
principle of the pear-shaped section, but when applied to the 
lifting hook having a long shank, the advantages are not verj' great, 
and in ca^e of ordinary standard pulling boats the question 
is hardly worth considering, especially in view of the very great 
difficulty of working out a satisfactory scheme of standardisation. 

If the scantlings shown in Table XIX. are adhered to, the 
lifting hooks will stand all the stresses which an open lifeboat is 



LIFTING HOOKS, ETC. 



299 



likely to experience, and will not raise doubt in the minds of 
ships' officers and passengers. 

Keel Plates. — There are at least three tjrpes of keel plates 
which are considered suitable for attachment to the shank of the 
lifting hook ; they are designed so as to stand a stress slightly 
in excess of that taken by the hook. " Out of sight, out of mind," 




- ELEVATION - 



- SECTION - 




■f 
2 



IL i. 



- PLAN - 
Fig. 1()9.— Type *' A " keel plate for lifting hook. 



can well be applied to keel plates which are usually fitted under 
the platforms of end lockers, but open to conditions where damp, 
etc., hav^e a detrimental effect on their lasting qualities. 

In the case of open lifeboats of Class I., 25 ft. to 30 ft. in length 
inclusive, which are not lifted by davits at the extreme ends, a 
very satisfactory type of keel plate is illustrated at Fig. 169. This 
consists of a steel plate cut out from an ordinary mild steel ship's 
plate with the jaws turned up to suit the lower end of the shank 



300 



SHIPS' BOATS 




of the lifting hook. This plate is fitted on top of the keelson and 
security is made by screw bolts with countersunk heads bearing 

on a'plate fitted on the 
underside of the keel, the 
nuts being hove up on 
the keel plate. Care must 
be taken to see that the 
ends of the screws are 
cut and slightly clenched 
over nuts. This type 
of keel plate has the 
advantage of a securing 
bolt fitted immediately 
at the centre of the 
shank of the lifting 
hook, in a direct line 
with the pull. The nut 
can be hove up securely 

Fio. I70.-Typo "B " keel plate. ^^^^ ^^^ ^^^ «* ^ ^^^ 

spanner. 
The heel of the shank can be formed into an eye to suit the 
jaws of the keel plate (as shown in section at Fig. 169), by working 

half-round iron into a 
bulb, (illustrated in Fig. 
167), then flattening the 
sides to suit the jaws and 
AifiTz -==i:z=rii a hole drilled to take the 

securing pin. 

Satisfactory tests have 

been carried out on hooks 

formed in this fashion, 

si^c^r^rcoo^re/rsoA^A with the result that the 

shank of the hook frac- 
tured before any impres- 
sion was made on the eye. 
The jaws of the keel plate 
prevent the hook from 
turning, and there is, 
therefore, no necessitv 
for a square neck in t^he 




PLAN 




Fig. 171.— Typo *'C" keol plat<\ 



latter to be fitted in way of the ganj^board. 

An iilt(»rnatiye method is often adopted in the Clyde district, 
by fitting two plato.s, the one forming the jaws being joggled 



y 



LIFTING HOOKS, ETC. 



301 



under the plate attached to the keelson in the ordinary way, 
having the centre bolt as a means of securing both the curved 
and flat plates. Very Uttle material is saved by adopting this 
principle, but a great saving of labour and cost is gain^. How- 
ever, the standard method is considered preferable. 

For lifeboats from 21 ft. in length to 24 ft. inclusive, a keel 
plate, illustrated in Fig. 170, is considered sufficient for the 
purpose. 

The results of tests prove the necessity to Umit the use pf this 
bridge pattern type of keel plate t/O boats not exceeding 24 ft. in 
length, or where there is a gi-eater dead load on the lifting hook 
than 39 tons. 

The shank of the bolt is screwed at the heel and secured by 
nuts fitted below and above the bridge, with a spht pin inserted 
through' the lowest nut and shank of the bolt. 

Care must be exercised by the smith to preserve a perfectly 
fair and level surface on the bridge clamp, for the reception of 
the securing bolts, and the nuts on the lifting hook. The arrange- 
ment is shown in Fig. 170. 

For lifeboats not exceeding 20 ft. in length, the shank of the 
lifting hook is carried through the keelson and keel, being 
screwed into a plate of the type shown in Fig. 171. The plate is 
slightly coimtersunk which allows the end of the shank of the 
hook to be well clenched over. 

Table XX. specifies the various dimensions of this type of 
plate to suit the different lengths of lifeboats. 

TABLE XX. 
Scale of Sizes for Keel Plates of Type '* C " fob Boats 20 feet in 

LENGTH AND UNDER. 

To be read in conjunction with Fig. 171. 



Ixjngth of boats In feet. 



Position of ScantlinKS. 



A 
H 
V 
I) 



E 



19 and 20. 



V 
r 

23" 

4.r 



17 and 18. 


16 and IjcIow. 


r 


r 


ir 


U' 


r 


r 


7 " 


7 ' 


n 


2}' 


2 * 


•*r 


4.r 



Arrangement of Securing Lifting Hook at Gangboard. — 

All lifting hooks which are fitted with keel plates illustrated in 



302 SHIPS' BOATS 

Fig. 169, viz. Type " A," need not ha,ve the square neck in 
way of the gangboard, but as the latter is somewhat weakened 
by being cut for the insertion of the eye at the end of the shank, 
the bolt is held rigidly in position by the aid of a steel plate, J in. 
in thickness, fitted in halves and recessed into the gangboard, 
being secured by six bolts with nuts hove up on washers fitted 
on the underside of the gangboard. The screws must be cut and 
clenched over the nuts. This arrangement is illustrated in Fig. 168. 

All Uftmg hooks having keel plates of Type " B " and " C " 
(Figs. 170 and 171), are required to be forged with square necks 
at the gangboard to prevent the hook from turning, and fitted 
with a plate recessed into the gangboard for half of its thickness, 
and well secured with four bolts, in the same fashion as previously 
described for the larger hooks. The type of plate used is shown 
in Fig. 168. 

It is necessary to give every support to the lifting hooks, and 
relieve the stress on the boat. For this reason the gangboard 
is made of the same material and thickness as the thwarts, 
having one end well bolted to the cross thwart and the other end 
well secured at the apron, and to a cross piece attached to the 
rising. A slight check is given to the gangboard when crossing the 
thwart, as illustrated in Fig. 83. 

The lifting hook should not project above the line of the gun- 
wale, otherwise it would prove a source of danger from passing 
ropes. At the same time there must be a sufiicient distance 
between the point of the hook and gangboard for manipu- 
lating the link on the block, and a Hmiting dimension has, 
therefore, been inserted at " G " in Table XIX., giving scantlings 
of lifting hooks. 

The forward hook must look aft, and the after hook must look 
forward, that is to say, both Ufting hooks look toward amidships. 

Considerations when Boat is lifted near the ends. — Special 
precautions must be taken when the lifeboats are lifted at the 
extreme ends, as in the case of Welin's Quadrant Davits. Reference 
should be made to Fig. 168. The fastenings of the deadwbod, 
keelson and keel need to be carefully considered in their relation 
to the securities of the keel plate, and so arranged that the 
fastenings to the frame combination of the boat may serve the 
double purpose of also securing the keel plates of the lifting hooks. 

The distance between the lifting hook and the stem or stem- 
post head doponda on the type of davit fitted to the vessel. 

In all cases, whether the Ufeboats are lifted near the ends by a 
special type of davit or by ordinary radial davits, the position of 



LIFTING HOOKS, ETC. 



303 



the lifting hooks should be obtained from the shipbuilder, before 
the frame combination is commenced, to enable every considera- 
tion to be taken into account in regard to the securities. 

When fitting the keel plate, the lugs should be of sufficient 
length to allow for the insertion of the pin to take the heel of the 
lifting bolt, as there is not much room to spare between the planks 
at the extreme ends, particularly forward. 

The securing bolts are arranged square to the keel plate so as 
to avoid tapered washers under the nuts. The heads of the bolts 
are square, or oblong, to suit the bearding of the stem, which 
prevents them turning. 

If it is desired to secure the bolts through the stem-band, the 
operation is one which necessitates great care. A batten mould 
is made round the face of the stem giving the position of the 
bolt holes, and the information is transferred to the stem-band, 
which of necessity has to be made of heavy scantling to provide 
sufficient bearing for the bolt heads. 



TABLE XXI. 

Scale of Sizes fur Keel Plates when Open Boats of Classes I. and III. 

ARE Lifted near the Ends. 

To be read in conjunction with Fig. 168. 



Length of boat in feet 



29 and 30 25-28 



21-24 



16-20 



Maximum dead load on lifting 
hooks in tons 

Thickness of keel plaU's in inches 

Width of keel plate in inches 



Securing bolts 



i Inner 
I Outer 



7-9 



H 



3 



2 (a I 
2 (a I' 



6-8 



2@i' 

2 (e r 



3-9 



21 

4® r 



2-3 

1 

2Ca.Y 

2 fe r 



Distance between centre of lugs and bottom of keel plate to be sufficient 
to allow for insertion of securing pin. 



Before the keel plates are made, the boatbuilder makes an 
inside mould to the curvatuce of the deadwood and keelson, and 
from this he makes another mould which the smith can apply to 
the keel plate durin^^ the operation of forging. The keel plate 
will fit dead-home to its work, if this precaution is taken. 

A good combination in way of the keel plates is shown in 
Fig. 168. The keelson is nin as far fore and aft as the deadwooda 



304 



SHIPS' BOATS 



will allow, suitable breasthooks and floors being fitted to strengthen 
the ends of the boat and support the combinations of stem and 
stempost. 

Bolts must be cut and clenched over the nuts, and this pre- 
caution attended to before the planking is commenced. 

Special attention must be given to the quahty of the dead- 
ly 



/^::^LimNG MOOM 



y/y 




THWAItr 



-A 



GANGBOARD 



• R/S/i^6 






7;>VjV4/rr 



^ 



SECrtONAL ELEVATION — 



pA 




— PLAN - 



Fig. 172. — Method of fitting the lifting hooks when lifeboat is carried in Wchn's 

overframo davit. 



woods, and care taken in arranging the details for the full thick- 
ness to fay on the planking. 

A scale of sizes of keel plates to suit the conditions under 
discussion, is given in Table XXI. 

Considerations when Boat is fitted in the Welin Overframe Davit — 
When lifeboats are lifted by and stowed in the " Welin " 
overframe tvpe of davit, the ([ucsticm of the position of the 
lifting hooks has to be specially cronsideied. 

The stowing chocks under the lifeboats must be fitted at the 
quarter lengths of the boat from the ends, to give adequate support. 



LIFTING HOOKS, ETC. 



306 



The chocks are fitted on the da vita in the case of the " overliame " 
type, so that the liftiu-; honks are immediately above the stowage 
chocks, i.e. situated one quarter the lenf^th of the boat from the 
ends. The position makes it very awkward to give adequate 
support to the hooks. It is therefore necessary to extend the 
gangboard to the second thwart from each end and well secure 
them with bolts, as shown in Fig. 172, 

Such a position for the lifting hooka is ideal to secure the best 
support for a loaded boat, but it interferes with the seating 
accommodation, and it necessitates the davit being made to 
the form of the boat. The difficulties referred to can be obviated 
by the fitting of a central supportmg chock, leaving the lifting 
hooka to be placed and secured in the usual position. This re- 
arrangement interferes somewhat with the actual purpose of the 
davit in giving an all-round view under the keel of a boat stowed 
on the Promenade Deck. 

Lifting Hooks at Extreme Ends ol Boats. — All lifeboats are 
arranged to be lifted, if possible, from the keel, but there may be 





Ifio. 173, Pro. 174. 

Lifting hooks for Bmall "Bquarr-sbrn" boats. 

circumstances which prevent this rule being adhered to, owing 
to the position and arrangement of the davits. The difficulty is 
only met in the case of small coasting steamers, where a " square 
stem" boat, or boats, are carried, when it becomes necessary 
to arrange for the lifting hooks to be fitted to the sternpost. 

The first cfmsideratiou is to strengthen the transom and 
sternpost head beyond the usual scautUngs. The latter is made 



306 



SHIPS' BOATS 



to mortice into the cross piece, and the quarter knecij must be 
substantial and well secured to the gunwale, transom, and cross 
piece with clenched fastenings. 

' Figs. 173 and 174 illustrate a type of lifting hook which has 
proved satisfactory in the case of small boats. The former is 
fitted to boats of about 20 ft. in length, and the alternative 
arrangement is suitable for smaller boats. In each case a stout 
plate is secured to the stempost to take the countersink of the 
heads of securing bolts, which is recessed into the transom. 
Care must be taken in forging the hook and drilling the holes for 
the securing bolts, to provide a fair surface for the head of the 
nuts. 

The arrangement at Fig. 173 involves a weld, and in each case 
the bolt must be subjected to an approved proof test. 

Wire Slings. — In certain classes of vessels, such as trawlers, 
steam lighters, etc., where the statutory regulations demand 



*toof< 




Fig. 175. — Method c»f lifting small boat when stowed under a derrick. 

only one boat to be carried, and which can be launched quickly 
on either side of the vessel, it is usual to fit the boat under the 
main derrick, and so arranged that if steam is off the winches, 
the boat can be swimg over the side without having to top the 
derrick. In such a case a suitable wire bridle is shackled t-o 
ring bolts well secured to the stem and stempost. 

The general arrangement of sling is given in Fig. 175. 

Mousing Arrangements for Lifting Hoolu. — Fig. 170 illustrates 
the McKays' Patent Safety Hook, supplied by Messrs. H. and C. 
Grayson, Ltd., Shipbuilders and Engineers of Liverpool, which 
is matle on the same princij)le as the McKays* Engaging and 



LIFTING HOOKS, ETC. 



307 



Disengai^ing Gear. This hook has found favour with many 
shipping companies. 

The purpose of a mousing arrangement is to prevent the falls 
from losing their grip of the hook when the boat is waterbome, 
and it is desired to keep the boat alongside the ship. Release 
is obtained by hinging the mousing gear by the aid of the 
lanyard. 

In Fig. 177 we have a very old arrangement which was 
originally termed the " Angrove " patent. The point of the 






I : ; I'.! 



Tiir 



I" • : 



UJ 



mr 



Fio. 176. — McKay's patent safety 
hook 



Fio. 177. — The Angrove patent 
mousing arrangement. 



lifting hook is formed as shown in the illustration, and a simple 
link is fitted on the hook which prevents the falls from jumping 
off, and when release is required, the tail-end of the link is lifted, 
which allows the head to clear the point of the hook. 

In both of these arrangements it is only a mousing gear that 
is fitted and must not be confused with a disengaging gear. 

Chain Slings. — The lifting arrangements for a large motor boat 
require special attention and consideration. Owing to the 
position of the machinery, etc., it is not always practicable to 
fit fixed hooks, and in order to adequately support the weight 



v^ 



*H'."?^' ^'' iT 



' « 



<»>» 



^ 

^ 



^' 










0t 










^ -= 



f 






^i*' 



T 

m 

« 



cur^^^ ^ 



1 1 






/; 



/: 



' i * 




^ 



^««^ « 






^ ^ 






* 



§34^ 



X 

V 
^ 

^ 



i 



•« r* • 




I 



/;/ tli'5 uiiuh\u*\ry arirl full numlif^r of p^Ts^^as m the boat when 
\numf, l"w«rMvl inVi til*, wabrr, chain .slings are usually fitted. 
A *J«;Uil»'^l iinii\\'jt*u\(ix\i of chain slings is given in Fig. 178, 



LIFTING HOOKS, ETC. 309 

and aizo.s have been insertfld whicli are considered suificient for a 
de^ load of 4 b>na, The forward Igr of the after sling ib arraufijed 
at the heel t« clear the propeller shaftint; by fitting a special 
shackle and keel plate as shown in the drawinj^. 

Steadying chains are essential fittings to prevent the hook from 
falliiv; and keep it in a vertical piano. 

The drawback t<i a system of chain sliajis is that the lifting 
hook is not a fixture, and there is a difhculty at times in making 
steadying; chains the exact length to suit the slings, with the result 
that there is a certain amoimt of slackness, quite sufficient to 
give the occupants of the boat a sense of insecurity. If there is. 
any movement, the boat will list to the side where the weij-ht is 
the greater. 

In the Admiralty service it ia the standanl practice to fit 
cliain slings to the motor and large pulling boats, but the con- 
ditions in a passenger vessel are very different. The whole of the 
persons lowered in a boat from one of H.M. war vessels, are trained 
and disciplined, while a large portion of the occupants of a lifeboat 
launched in an emergency from a passenger or emigrant vessel, 
would be in a condition of excitemeqt, and the difficulties of 
controlling and releasing the boat would be accentuated by the 
crowded conditions. 

There ia little doubt that chain slings can be arranged to sup- 
port the weight of the boat, etc., to better advantage than can 
' B obtained from fixed lifting hooks, but taking all the circum- 
stances into consideration, it is preferable to fit the latter when 
the arrangements will admit. 

Cliain slings are always fitted to the open boats of Class II., 
and pontoon boats of Classes Ic, IIb and llo, which have collap- 
sible bulwarks. An arrangement of fixed hooks in these types of 
boats and those of Captain Murray's nested boats woidd seriously 
interfere with the stowage arrangements. The various details 
associated with the lifting gear of these boats have been dealt 
with in their own particular section. 

Robinson's Patent Common Hooks.— -Where it is unnecessary 
to fit a simultaneous releasing gear to ships' boats, a very 
reliable and convenient form of hook has been designed by 
Messrs. Robinson and Co., Ltd., of Chiswick, London, which 
enables the two ends t)f the boat to be unhooked separately by 
hand by two men. 

Illustrations of the hook are given in Fig. 179 and 180, from 
which it will be seen that the book is of the fixed or no7i-tumblinq 
type, and attached to theshankbyabolt Wabovethegangboard. 



no SHIPS' BOATS 

Tfe —till do mat adrocate tkw m t 
maiilir its mCg faan «f book for indepcBdcA I 

A i|M(Mlhr deN^aed dwckfe G tt made to fit tfe haafc, i 
■ cmuieetod to Um tag bolt of tke lava tadde Uoek. Tb ' 
pnnrcat tlie fab b wwn^ detacbcd £idib tlw hook. « «a^ 
■HMWDfE attaagpnmi m fitted, h sbnn >t T. Wbn it m 
neea—ry to nleMe tlie falk btHB tbe hook, • Uunn deviee at K 
M ca*df opetated and aflavi tlie lAacUe to cleat tbc hook. 





Fig. 179 tthiiwn the mousing gear in position to prevent 1 
faliH Irom unhooldng, and Fig. 180 shows the gear out of a ' 
which prevents any obstruction to unhooking, or hooldcg ( 
the "hsekle attached to the lower tackle block. 

This type of hook hsa been adopted by the Britiah Admiralty 1 
for mII biiatK of the non -emergency cla.ss which are carried uodcv T 
davitA ; it liax been litted in a large number of Royal fleet i 
Auxiliaried and merchant ve^HcLs, and from the perwnal obaerva- J 
tion of the writer, has proved very satinfactory. 



BOATS' ENGAGING AND DISENGAGING GEAR 311 

SECTION B.— BOATS* ENGAGING AND DISENGAGING 

GEAR 

The question of releasing a ship's boat from the overhanging 
fall9 attached to the davit blocks, into the water, is one of very 
great importance. Accidents have occurred to both passenger 
and cargo vessels through the inefficient means provided for 
quickly detaching the boats from the lifting hooks. 

Considerable difficulty surrounds the subject when dealing 
with the equipment of lifeboats on vessels in the Mercantile 
Marine Service. 

Where it is considered necessary to fit disengaging gear to 
boats carried on war vessels of the British Navy, a standard 
pattern is adhered to. The reason is veiy obvious. Sailors are 
trained to use a particular type of apparatus, which obviates 
many mistakes, and considerably minimises the risk which is 
associated with the operation of handling a gear by men un- 
acquainted with the design. 

It is not suggested that the Bqard of Trade would go so far 
as to set up a definite standard of design, and thus hinder the 
scope of the inventive genius of the private individual, but such 
a scheme would, nevertheless, be of great advantage to the 
mercantile marine and increase the confidence of passengers 
in the ability of the boat's crew to successfully manage a lifeboat 
in difficult circumstances. 

The question that first comes to one's mind in dealing with this 
subject, is whether it is necessary or essential to fit a disengaging 
gear to a lifeboat. 

In accordance with the Rules for Life-saving Appliances, 
means must be provided for speedily, but not necessarily 
simultaneously or automatically, detaching the boats from the 
falls. Where the falls are detached by hand after the boat 
becomes waterborne, a suitable ring or long link is fitted to' the 
lower blocks, so as to provide for the easy detachment from 
the fixed lifting hooks in the lifeboats. 

The statutory regulations, therefore, do not insist on a 
mechanical means being fitted for releasing the boat from the 
blocks. 

There have been many types of apparatus on the market 
which were supposed to satisfactorily release a boat under service 
conditions, which have failed when actually tested at sea ; 
consequently ships' officers are somewhat sceptical as to the 
efficiency of some releasing gears. 



312 SHIPS' BOATS 

Many desi<i;n8 result in confusion and lack of confidence on 
the part of the boat's crew. The means for efEecting release is 
sometimes provided by hauling on and at other times by letting 
go a line. Where members of the crew are not constantly 
attached to the one ship, these differences of design, in the operat- 
ing movement of the various gears, create difficulty. In any case 
a clear and simple description of the particular gear fitted to the 
boats should be placed ne^r the lifeboats, and the crew thoroughly 
trained in the use of the mechanism, under sea-going conditions. 

The nece^ity for fitting a mechanical means of simidtaneously 
releasing the lifting hooks from the falls, appeals to every person 
who possesses sea experience, but as to the most satisfactory type 
of gear, there is a difference of opinion, for associated with the 
releasing operation is the question of seamanship in controlling 
the boat and preventing her from being drawn under the stem 
of the vessel and coming into contact with the propellers. 

It is of paramoimt importance when a boat is lowered into the 
water from davits, that it should be cleared from the falls as 
quickly as possible. 

When release is actuated by hand, the process lends itself to 
difficulty and danger, unless the two hooks are released together. 

K the boat is lowered when a heavy sea is running, there is a 
common danger for the forward block to drop below the lifting 
hook and so become released, and the after hook to remain engaged 
with the link in the block, unless an arrangement of mousing 
the hook is fitted, which prevents the link on the block from 
freeing itself. The method must be simple and effective, for the 
reasons already explained. 

If the ship still has way and it becomes necessary to launch 
the boats, then the difficulty of releasing the falls by hand is 
considerably increased ; if there is a towing stress on the forward 
hook, the operation of disengaging the falls is accompanied with 
some risk, unless the preliminary precaution is taken, before 
launching the boat, to secure the painter to a cleat or stanchion 
on the deck well forward of the davits ; so that when the boat 
becomes waterbome, the effect of the towing stress on the blocks 
can be relieved by hauling on the painter, which would then 
allow the link to clear tlie liook. Here again, tlie question of 
scamansbi]) conies in, and men slunild be trained to disengage the 
boat under those conditions, to j)revent, as far as ordinary cir- 
cumstances will allow, the lifeboat from being swamped in a 
storm. 

Comparatively few car^o vessels are supplied with boats 



OATS' ENGAGING AND DISENGAGING GEAR 313 

fitted with enfjagint; aud disengaging ^ear, but owiiit;; to the ex- 
perience f;ained during the European War, the majority ol the 
standard vessels conetnicted in Great Britain are fitted with 
lifeboats having a mechanically- controlled releasing gear. 

Most of the leading passenger liners, telegraph, and pilot 
VCBS^, have their boats fitted with disengaging gear. 

General conditions are now laid down by the Board of Trade 
before boats' engaging and disengaging gears can be used as part 
of the statutory equipment of a ship. They are as follows : — 

" (1) All disengaging gears must be so arranged as to ensure 
simult-aneous release at both ends of tiie boat. 

" (2) The means of effecting release must be placed aft, bo as 
tn be under the personal control of the coxswain in charge of thtt 
boat. 

" (3) The gear may be of a type affording release before the 
boat is waterborne, as well as when the boat is wholly or partially 
waterborne ; or alternatively, it may be of a type affording release 
only when the boat is wholly or partially waterborne. In either 
case it must be safe, speedy, and reliable in action. 

" (4) The action should be such that the hook offers no resist- 
ance to release should there be a towing strain on the falls. 

" (."5) The hooks must be suitable for instant imhooking by 
hand. 

"(fi) The gear and mechanism for effecting release must be 
such and so arranged as to ensure the safety of the boat inde- 
• pendeutly of any " safety-pins." 

" (7) The means for effecting release may be by hauling on, or 
letting go a line, or by a lever. If release is effected by a pull 
upon a hne, the latter must be properly cased in. Rods or other 
connections between hooka must also be cased in whenever this 
is necessary for safety or for the efficient action of the gear and 
the protection of persona from injury. 

'■ The fairleads must be properly arranged to prevent the bnea, 
which shotdd be fitted with chains where necessary for efficiency, 
from jamming or nipping, and must be strongly attached to 
permanent parts of the boat. 

" (8) Such parts of the gear as would otherwise be likely to 
set fast by rust or corrosion must be made of non-corrodible 
metal. 

"(9) No part of the gear taking the weight of the boat is to be 
made of cast metal. 

" (10) The scantlings and proportions of all parts taking the 
weight of the boat, should be such as to provide a factor of safety 



314 »SHIPS' BOATS 

of at least four, with a dead working load equivalent to the total 
weight of boat, equipment and full complement of persons." 

All new sets of disengaging gear must have a sample of each 
size submitted for a proof test equivalent to the total weight, 
including equipment and full complement of persons, of the largest 
boat for which it is claimed the gear is suitable. 

This test is continued to the point of fracture in order to 
determine the approximate factor of safety. 

Lowering and disengaging tests uniJi a loaded boat are also 
carried out under the following conditions : — 

(a) Boat fully waterbome. 

(6) Boat partially waterbome, one end being out of the 
water. 

(c) In the case of a gear which can be released before the 

boat is waterbome, additional tests with the keel of the 
boat just clear of the water. ' 

(d) The efficiency of the hooks and gear is also tested by well 

jerking the boat in the tests (b) and (c). 

If the results of the tests are satisfactory a certificate of 
approval is granted to the owner or patentee. 

From a practical working point of view, it is generally con- 
sidered that boats' disengaging gears should be divided into two 
distinct classes — 

(1) Those which can release when the vessel is under way at 
ordinary or usual speed. 

(2) Those which release when the vessel is almost at rest. 

In deaUng with the first namexl, the gear should be such that 
when the vessel is steaming at the rate of say 15 knots, the boat 
could be released at the particular moment desired by the 
coxswain. 

With a heavy sea mniiin<s it is verv desirable that the release 
should be instantaneous and simultaneous at both ends. The 
operation of release must be under the control of one person 
thoroughly acquainted with the mechanism and well skilled in the 
handling of a boat when launched under difficulties. 

On all well-equipped passenger vessels, two emergency or 
** accident " boats are carried near the navigating bridge, one 
on each side of the vessel, swung out while at sea, brailed into a 
boom and ready for immediate use. This is a regulation issued 
by the Steamboat Inspection Service of the United States of 
America, and is adhered to in most British passenger ships. 

The purpose of these boats is that in the case of persons falling 
overboard, or for other reasons of emergency, they can be 



BOATS' ENGAGING AND DISENGAGING GEAR 316 

rapidly manned and lowered into the water at the word of 
command from the officer in charge on the bridge. 

Special men are selected for manning these particular boats, 
and the number of crew lowered is only sufficient for the proper 
handling and navigation of the boat. The necessity for lowering 
the boats usually occurs when the vessel is under way with 
considerable speed ; it therefore stands to reason that the men 
qualified to manage the boat should be well trained and efficient, 
and that the type of releasing gear should be such that it can be 
** sUpped *' before the boat becomes waterbome, for any towing 
stress on the boat when the vessel is rapidly steaming ahead would 
inevitably bring disaster. 

The enormous weight of a loaded Ufeboat brings a severe 
stress on most types of gear which allow the boat to be released 
before being waterbome. 

The second type of gear referred to, viz. that which releases 
when the boat is waterbome after the vessel has come to rest, is 
generally considered to be more suitable and better adapted to 
the needs of vessels of the Mercantile Marine Service. 

In case of disaster, when it becomes necessary to lower the 
lifeboats into the water, they would probably be crowded with 
passengers in a condition of nervous excitement, having just 
sufficient crew to man the boat for rowing. Under these con- 
ditions a gear which can be released before the lifeboat reaches 
the water by a slipping movement, or having an adjustment of 
safety-pins, would be a source of danger to the occupants, 
considering the great distance between the promenade deck and 
the water-level of the largest passenger vessels. 

The purpose of lifeboats/ apart from the emergency boats, is 
to transport the passengers from a vessel which is probably 
foundering and has little or no way on. 

During the operation of transferring the passengers to the 
boats, the personal element always comes into operation and has 
to be carefully considered. It may be possible, under the 
conditions of panic, for some boats to get launched unattended by 
sailors qualified in the use of releasing the falls from the boat, 
and if there is a heavy sea mnning on a dark night, the 
congested state of the boat may prevent simultaneous action 
between the operators at the lifting hooks, and the action of inde- 
pendently releasing the falls will be accompanied with considerable 
danger. It is, tlierefore, considered by ships' officers that a simple 
device for simultaneously releasing both ends of the boat, and 
under the control of a responsible, person aft, is greatly to be 



316 SHIPS' BOATS 

preferred, and not so liable to accident, as the independent 
release. 

The majority of the " waterbome " gears will not successfully 
release under a towing strain in a boat loaded with the full 
number of passengers. The various patentees claim their gears 
can satisfy the requirements, but it is the candid opinion of the 
writer that if a boat must be released when a towing stress is in 
operation and cannot be avoided, then the first type of gear 
referred ido is considered the most suitable, and it possesses the 
great advantage that the boat can be dropped at the psychological 
moment to catch the crest of a wave, and thus avoid being 
swamped. 

However, there is considerable doubt as to which is the better 
type of gear to recommend for lifeboats of passenger vessels ; it 
largely depends on the particular d^ign or pattern, and each 
should be very carefully tested and treated on its own merits. 

Mills* Patent Engaging and Disengaging Boat Gear. — Messrs. 
William Mills, Ltd., Engineers, of the Atlas Works, Sunderland, 
manufacture an apparatus for quickly releasing ships' boats from 
the davit falls, and which has found much favour in Great Britain 
and other countries. 

A general arrangement plan of the gear is shown in Fig. 181. 
It consists of a straight shank lifting bolt,* the heel of which is 
formed into an eye, or screwed to fit the particular type of keel 
plate suited to the size of boat. The upper portion of the shank 
is forked and well secured to the gangboard by nut and screw 
bolts. Ordinary screws are considered unsuitable for the purpose. 
Pivoted to the fork is the lifting hook, which is heavily weighted 
at the lower end. 

The hook does not project above the gangboard, and the 
possibiUty of ropes fouling the boat is therefore minimised. 

The position of the head of an ordinary lifting hook above the 
gangboard is about 10 in. in a 28-ft. lifeboat, or 2 in. below the 
gunwale. To maintain the same conditions of safety when a boat 
is lowered* with the lull number of persons, it seems essential to 
fit the gangboard in such a position as to allow the lifting hooks, 
with the Mills' Patent Gear, to be in the same relative position 
as the standard type of lifting liook. 

The weighted lever maintains the hook in its upright position. 
Attaclied to the block is a circular swivel, link or eye, which 
engages tho hook bencmtli the level of the gangboard. The 
opcM'ation of connecting the hook to the link can be independently 
p(Mfornied by hand at eacli end of the boat, or the hooks can be 



BOATS' ENGAGING AND DISENGAGING GEAR 317 



brought into position simultaneously by the coxswain in the 
stern-uhcots. 




Attached to tlie w«if;hted end of the hook is a chain and wire 
lead, which runs tlirowgh fairleads secured to some permanent 
j>art of the structure. These releasing wires and chains have 



318 SHIPS' BOATS 

usually been led below the thwarts and side seats, or below the 
thwarts and in front of the tank cleading. This is a matter of 
detail, but with the lifting hook brought up to the same height 
as a standard hook, it is a more convenient and practical arrange- 
ment to bring the leads from the hooks along the sides of the boat 
above the thwarts. This is the general practice in fitting out 
boats in the United States of America when Mills' gear is specified. 
In any case, the fairleads must be well secured, and so fitted as to 
make the leads as easy and direct as possible. 

The whole of the apparatus must be cased in to prevent any 
possible interference from passengers in the boat. 

The disengaging operation is under the personal control of the 
coxswain in the stem-sheets. 

The boat cannot be released until it becomes waterborne. 
Immediately the weight bl the boat is reUeved from the blocks, 
the releasing handle, secured to the chain leads, is jmlled, which 
raises the weighted lifting hook lever and draws back the point 
of the hook clear of the bridge piece attached to the gangboard, 
and thus allows the link of the block to free itself. 

Great care must be exercised by the boatbuilder in fitting 
up the gear, to see that the length of the chains is adjusted 
at the releasing handle, so that both lifting hooks are operated 
simultaneously. The patentee depends on the builder following 
out the printed instructions issued with each complete set of 
gear, otherwise a careless disregard to the essential points to be 
observed, places the occupants of a boat in great danger. 

The following information will be useful in selecting the 
correct type of gear for a particular weight of boat : — 

Type 

A 
B 

C 
D 

Dl (steel) 

ROBINSON'S BOAT-RELEASING GEARS. 

These are of two kinds, to correspond with the two classes into 
which the makers contend that all ships' boats should be divided, 
viz. : — 

1 . Em^rcjetwji Bonis, for lowering instantly while the ship still 
retains high sjmmuI (chiefly to pick up a man overboard). 



Weight of boat 




Size of swivel 


(with full complement). 


ring in bloek. 


. 2*7 tons. 




y iron. 


4*1 




r 


. 5-5 „ 




r steel. 


. 4-9 „ 




1" 


. 7-0 „ 




V 



BOATS' ENGAGING AND DISENGAGING GEAR 319 

Such a boat has (and, of course, needs) the advantage 
of skilled control, and is lowered with only a few men 
on board. 

2. Ships* LifeboatSy for saving large numbers of passengers 

and crew from a stranded or foundering sjiip, which is 
presumably either stationary or has little way on. 

3. There is a further class of boat used either under safe 

conditions, as in harbours or rivers, or by people too 
imskilled to be trusted with any simultaneous gear, or 
belonging to owners for whom the cost of such gear of a 
reliable pattern is prohibitive. The Robinson patents 
* provide for this class of boat by a special form of 
common hook, not a releasing gear in the proper sense. 
Reference has already been made to this in Section A, 
Part VI. 
Robinson's Navy Releasing Gear is designed for the Emergency 
Boat. It is, and for many years has been, carried in all ships of 
the British Navy, and is no less suitable for the two emergency 
boats which first-class passenger vessels ought to carry in addition 
to their " lifeboats." It compUes with the following require- 
ments, which are practically those which the Admiralty formulated 
many years ago : — 

(a) It must be impossible for one end of the boat to release 

without freeing the other. 
(6) She must release equally well whether waterbome or 
before reaching the water, at the discretion of the man in 
charge — because she is liable to be lowered with enough 
way on the ship to swamp the boat if release is delayed 
until after she is waterbome. Release shortly before 
reaching the water involves no danger if the boat is 
well handled : (** Automatic " action on becoming 
waterbome, which means the automatic opening of the 
hooks as soon as the boat's weight is off the tackles, 
is obviously inappUcable if the ship is moving fast, as 
the boat is then liable to be totued by the tackles, which, 
therefore, are no< reUeved of her weight.) 

(c) The hook must be moused against accidental imhooking 

if the boat is kept lying alongside, but the mousing must 
offer no hindrance to sUpping or to hooking-on, or to 
unliooking by hand if desired. 

(d) The hook must be in the boat, not on the tackle. 

In the Navy the emergency boats (formerly called the 
" quarter-boats " because one was carried on each quarter) are 



320 SHIPS' BOATS 

large cutters fitted with " cliairi MJinf^a," for which a spi^cial design 
of the KobinsuQ gear is used, The pitttera (known as Type C), 





which is fitted in some other classes of Navy boats, is more 1 
suitable for mercantile vessels, and is shown in general arrange- • 




ment in Fig. ISli, while the hook is sJiown in elevation in Fig. 183 
(with " safety-pin " in place) ; in section in Fig. 184 (with 
safety-pin removed) ; in section (after slipping) in Fig, 185. It 




BOATS' ENGAGING AND DISENGAGING GEAR 321 

■ will be seen that the weight of the boat tends to rotate the 
tumbling hook H, which, however, is retained in place by the 
lever K, the latter being held to its work by the direct pull of the 
short length of wire-rope M. The ropes M of the two hooks are 
drawn together by a light chain fore-and-after NN, by means of 
the tackle shown in Fig, 182. On releaainij tbe fall of the tackle 




— Section. Relcuwd. 



both hooks are set free to " tumble " and ehoiild do so instantly 
if the weight of the boat is still on tbe tackles, or if there is even 
such a pull upon them as is caused by the rise and faU of the 
waves, or merely by pushing the boat away from the ship's side, 
T is the mousing tumbler, wbich lies in the mousing position by 
its own weight, but lifts out of the way (and then falls back again) 
to admit the ring shackle G when hooking on. (G is attached to the 
lower tackle block.) T can be turned out of the way for unhooking 



332 SHIPS' BOATS 

by ItaTul by a touch of the finger upon the httle lever Q. It offers 1 
no obstacle to slipping. The aectiona show the naval brass pins ' 
tor the hook, etc., and the shouldered rivets holding the two side- ' 
plates apart, some of which serve as stops for the moving parts. 
The " fin " on the top of the hook and the projection below, and 
that on the lever K, all serve minor purposes in ensuring safe 
working. W is a bayonet-joint pin (or bolt and nut) to enable 
the hook to be removed if desired, leaving only the head of the 
keel-bolt above the deck. Another pattern is made in which the 
hook stands less high above the deck. It will be seen that the 
fore-and -after is above the thwarts, well in sight, and that no 
one can do any harm by hanging on to it or stumbling against it, 
as that can only tighten the pull which prevents the hooks from 
tumbling ; this marks the advantage of slipping by " letting-go " 
rather than by pulling, for a rope which has to be pulled can 
always, in effect, be pulled accidentally from either of the 
causes mentioned. The fall is given a turn round a thwart, 
cleat, or bollard, to make it easier to hold. 

RQblnson's Waterborne Releasing Gear (Hercbant Service) 
is a new patent designed for life-saving boats, in the sense of 
boats lowered to save the passengers and crew, and to meet the 
following conditions over and above the condition that it must 
be incapable of release unless the boat is fully waterborne ; — 
(fl) Such a lifeboat is hable to be crowded with helpless and 
frightened passengers, and any fore-and-aft connection 
above the thwarts may, therefore, be subject to such J 
interference as to make successful action impossible. The ] 
connection must be down below, thoroughly screened 
against interference or contact with the passengers' feet. 

(b) Skilled control, such as is always available in the Navy, 

cannot be depended upon in all the boats of a large . 
passenger vessel, and the less skilled man who may be , 
in charge cannot safely be trusted with the power to 
slip before reaching the water, In the confusion of I 
darkness and crowding, and amidst the terrors of s 
sinking vessel, tlie boat might be slipped too early, with I 
disastrous result. 

(c) The two hooks must be connected so rigidly that they not 

only move together, but so that moving one back to 
the hooking-on position inevitably move* the otiiet aa 
well, Constant readiness for hooking-on is important f 
in view of the frequent boat drills it is desirable to 
courage. In Messrs. Robinson and Co.'s view the ] 



324 



SHIPS' BOATS 



connection between the hooka ia the cmx of t&e mM 
and it will be seen that very special means are employed. 
The hook itaelf is shown in Fig. 186, and on a larger scale, 
in section, in Figs. 187 and 188. 

The forward hook ia similar to the after one, but without the 
prolongation of the link R to form the releasing lever U, which 
is required only at the after end. When the lever U ia raised the , 




link B is drawn downwards and cant^ the hook H backwards, so J 
as to free the ring-shackle attached to the lower block G 1 
1 188). The treeing action is assisted by the lateral 1 
movement of B, which first moves backward and then comes j 
forward to push ofi the shackle. 

The Navy mousing tumbler T (slightly changed in form) ia I 
retained, and Fig. 187 shows how it lifts out of the way in the act 1 
of hooking-on. Fig. 188 shows the shackle completely released I 
by the continued movement of the lever and the link B. 



BOATS' ENGAGING AND DISENGAGING GE.Ut 325 

Two galvanised short^lmlc crane chaina, X and Y, are attached 
to R, Piilliiif; down the link B involves pulling up chain Y, the 
other end of which is attached to the link (B) of the forward hook ; 
hence both Uoka are pulled down, and both hooks are freed, by 
the same action. Also, on the lever being again depressed, both 
hooka, through the action of the chain X, are re-set for hooking-on. 
The catch Z, which is withdrawn by the lifting of Q in taking 




W:^ 



Beleaaed. 



hold of the releasing lever, preventa the latter from being raised 
by any accidental cause, The arrangement of the lever can be 
varied to suit the construction of the boat. 

An ideal connection between the two hooks, to ensure absolute 
simultaneity in their movement, would be given by a single rigid 
rod along the bottom of the boat, working both hooks by a 
suitable arrangement of links and bell-cranks, or the like, all 
carefully cased in against injury or interference by the crowded 
feet of the passengers. But, unfortunately, the modem practice 



326 SHIPS' BOATS ^^H 

of hanging boats from points very near their ends, Bometni 
up the curve of the stem or the deadwood, makes such a c 
tion difficult and incunvenicnt. Messrs. Robinson and Co., 
therefore, use chains (two, since chains can be used in tension 
only, and movement both ways has to be provided for), and case 
them very simply and conveniently by running them through 
lubes: 1^ in. galvanised gas-pipe of good quality is suitable. 
Each chain has to alter its direction by 180°, and if this involved 
the use of bell-cranks, or passing the chains over pulleys, there 
would be no gain from iising them. But experience has shown 
that if such tubes are bent to very easy curves, chains will travel 
in them with scarcely any more friction than if taken round pulleys, 
and the adoption of this system has resulted in an arrangement 
which is exceedingly neat and simple, while the protection of the 
chains and their immunity from damage or interference is practi- 
cally perfect. The tubes can be partly filled with grease. 

Though it ia impossible for the coxswain to move the releasing 
lever while anything like the weight of one end of the boat is on 
either tackle, there is enough leverage to overcome a moderate 
towing strain, giving a pull of say a few hundred poimds. It is, 
of course, assumed that no one would attempt to lower a heavily- 
weighted lifeboat while the ship is still moving at a really con- 
siderable speed. 

The tubes are clipped to the sides of the keelson and to the J 
linlcs A (which take the place of keel bottE), and it is not neceesaiy j 
t<j avoid bends if the latter are e^iay. 

It is interesting to note that in the maker's opinion the I 
widely different services to be performed by the Emergency boat 
(for the man overboard), and by the general Life-aaving boat, 
require not only different, but diametrically opposite treatment, 
In the one case release deferred until the boat is waterbome is 
dangerous and unsuitable ; in the other it is ossectial to safety, 
Nearly every feature of the gear is reversed in the two cases, and 
the reasons given for this are weighty, while in the case of the j 
Navy emergency boat they are confirmed by the succeeslul 1 
practice of many years, 

THE STEWARD DAVIT AND EQUIPMENT C0RP0RAT10H*S 
PATENT BOAT RELEASING GEAR. 



The action of this gear is quite different to those previously J 
described : chains and wires are dispensed with, the operating 1 
device being direct. The arrangement consists of a trippii^; 1 




BOATS' ENGAGING AND DISENGAGING GEAR^P 

or tumbling hook, and as will be seen from Fig. 189, these hooka 
are pivoted to a bracket which is strongly attached to the stem 
and stempost. The British Board of Trade have strong objections 
to lifeboats being lifted from the extreme ends, but this gear, now 
under review, can easily be made to comply with all the require- 




Fii). I8'J.— Thu Stfward UjiviC and E<iuinmeii 
rL'lL'iising g<.ar. 



ments whereby the stresses are taken by the frame combinationfl, 
and the heel of the Uf ting-hook shank secured to the keelson, keel, 
etc. The hook is operated by a shaft or standard pipe running 
the length of the boat, Brackets with shaft bearer's are secured 
to the keelson in a rigid fashion, but with suiUcient clearance and 
flexibility to prevent binding, should the shaft or keelson com- 
bination become distorted. At either end ol the pipe there is an 



338 SHIPS' BOATS ^^H 

eccentric, which opetatea a cam. The latter is attached to a ^ 
vertical shaft, the upper end of whicli is forked and fitted with a 
metal roller. When the horizontal shaft is rotated by the operat- i 
ing or releasing lever, the vertical shaft and fork are drawn down, ' 
giving release to the honk which is free to clear itself from the 
shackle attached tu the davit blocka, even when there is a towing j 
strain on the falls. Fig. 189 illustrates the position of the hook 
after release. I 

The working parts of the gear are made of non-corroaive metal 
or of galvanised steel. The hook pins and the rollers attached 
to the fork, which are secured to the upper ends of the vertical 
ahaftfi, prevent the hfting hook from tripping before the coxswMn I 
operates the lever, and are made of special " monel " metal. 

The whole operation of releasing the boat from the falls 
becomes extremely simple with this particular design of gear, as I 
it is direct in action ; all the fittings are open for inspection, and 
can always be seen. No danger is present during the operation 
of lowering the boat, imless the gear collapses or an individual 
deliberately raises the operating lever, but the patentees appear 
to have B^eguarded their own interests as well as those of the 
passengers, in this respect. 

The boat can be released by hand when waterbome, in the 
usual way, and mousing arrannements are fitted on the hooka ] 
to prevent the links on the blocka from premature detachment. I 

The requirements of the British Board of Trade are very severe, 
and it will be of general interest to the reader to give an outline of 
tests carried out in the presence of the writer on the s.s, Free- 
man in Messrs. Robins' Ship Repairing Yard at BrookljTi, New 
York. 

A 26-ft. steel lifeboat capable of accommodating about 
3-5 persons was fitted with the Steward Patent Disengaging Gear. 
The boat was under the Steward Patent Davit. 

The order of the tests was as follows ; — 

1. The boat was lowered into the water, and when fully 
waterbome the gear released the boat from the falls. 

"1. The boat was hoisted well clear of the water, lowered, and , 
checked suddenly, jerked fore and aft by means of the falls, and i 
then released when the keel was about two feet from the water- ' 
level. (See Fig. 190.) 

3. The boat was partly waterbome, and the operating lever ■ | 
moved slowly, to prove that both ends were released satisfactorily. 

4. The after end of the boat was waterbome, and the forward I 
end lifted out of the water, to demonstrate the effect of a towing A 



BOATS' ENGAGING AND DISENGAGING GEAR 329 

strain on the forward hook. No difficulty occurred in the 
releasing operation. 

5, The boat, when floating and ei^aj^ed with the falls, was 
unhooked by hand, while the gear remained locked. Blocks 
were again engaged by hand with the hftinj; hoijks. tn demonstrate 




that the whole operation could be performed by two men in a 
very few seconds. 

6. Witi the boat fully loaded with over thirty men, and a 
number of the occupants standing on the fore-and-aft hollow 
shaft or pipe, the gear easily released the hooks. 

7. The final test was a severe one for the davits. The fully 
loaded boat was raised until the keel became well clear of the 
water ; under this condition the operating lever was raised; and 



330 



SHIPS' BOATS 



the boat released without difficulty. The photograph shown iif 
Fig. 190 illustrates the position of the boat immediately afttrfl 
release. 

There are several other gears on the market which appear^ 
fulfil the requirements of the British Board of Trade, but it is 
considered that sufficient reference has been made in this section to 
actual gears now in operation, and also tu the teste carried out, to 
give the reader a general idea of the requirements which enable 
a boat to successfully take the water after being released from 
the lower blocks attached to the davit falls. 



SECTION C— CONSTRUCTION OF BUOYANCY AIR-CASE 

All lifeboats must be in possession of a certain amount of resetvi 
buoyancy. The open hfeboats are fitted with buoyancy air-j 
cases along their sides, and the pontoon lifeboats are dependeafc; 
on a number of watertight compartments, which are an integral! 
part of the hull. 

The internal buoyancy tanks of Class Ia and Ib lifeboats aw; 
usually constructed of the best quality copper or yellow metali 
of not less than 18 oz. to the superficial foot. The^ are placi 
along the sides of the boat under the side benches. 

It is admissible to fit buoyancy air-tanks at the ends of a boal 
but never in the bottom. Although it is an inconvenience to fit 
a buoyancy -tank at the forward or after ends, as it interferes wif ' 
the stowage of equipment and the fitting of the lifting hooks, yi 
an air-case in the fore end has the advantage of giving Ufting powi 
to the boat should the latter become flooded with water. 

Wlien cases are fitted in the ends, they should be separate^l 
into two distinct portions on each side of the lifting hool 
to prevent the latter being unshipped when it becomes 
to remove the buoyancy air-cases for inspection. 

The method of construction of buoyancy air-caaes is briefi^ 
described as follows : — 

The size of acopperor Muntz metal sheet supphed to the tank- 
maker is usually 4 ft. by 3J ft., and weighs about 25'2 om., 
which conforms to the requirements of the Board of Trade, 
18 ozs. to the superficial foot. 

From the information supphed to him by the boat-buUd< 
the tank -maker knows the internal capacity of the boat. In tiiia 
connection it is well to remember that all open lifeboats vi 
Class Ia should be coustmcted with a coefficient of not leas thaa 
6i, which means that the internal capacity divided by the^ 



>za.. 



mk JL 




CONSTRUCTION OF BUOYANCY AIR-CA8E8 331 

apparent unit of capacity exceeds the actual number of 'persona 
which can be comfortably seated in a boat. As an example, 
■ take an open lifeboat 28-0' X 8-5' X 3y', which will give a 
capacity of about 540 cub. ft. The number of poraons which 
a be appropriated ia about fifty. The number of cubic feet 
of buoyancy-tanks must therefore be fifty-four and not fifty. 

The amount of buoyancy-tank capacity depends on the boat 
capacity, and not on the number of persona carried. 

The tank-maker usually haa standard moulds to suit the shape 
of the bilge of ordinary pulling boata, but in the case of motor 
boats, open boats of Class 11. , and nested boats, it is necessary 
to make special moulds to suit the form of boat. 

The end sections of the metal air-cases are cut to the shape 
given by the moulds, with the addition of a margin of about J in. 
to allow for the single hook joint. A gauge mark is then made 
round the three edges, and the comers cut as shown in Fig. 191 A. 

The sectional pieces are then placed in an edging or flanging 
machine, whicli flattens and stifTeus the material. The gauge 
marks on the straight edges are set to the grips of the machine, 
and by the aid of the lever brought up to the horizontal position, 
the straight edges are turned up to a rij^ht angle. The curved 
edge has tu be treated separately by hand at the bench, until the 
section takes the form as illustrated in Fig, 191 B. 

The edges of the end sections are turned over by hand in 
hook fashion as shown in Fig, 191 o, ready for the reception of the 
sides of the air-cases. 

The sides of the metal air-cases usually require two longitudinal 
joining seams, which are brought together with double hook 
joints. The material is placed in the edging-machine and the 
hook formed in the one movement by the operation of the lever 

I brought to the vertical position. The edges of the two separate 
sheets of metal are thus made tu hook into one another as shown 
in Fig. 191 d. The completion of the double hook joint is made 
with a stamping-tool, which brings the hooks into close joint, 
and the sides into hne as shown in Fig. 191 b. 
In the final treatment a wooden mallet is used, followed by a 
steel hammer which makes a tight joint. 
Similar procedure is followed in making the coimections of the 
aides and end sections, except that the joints are only of the single 
hook type. 
All the joints and comers are carefully soldered. Great care 
should be taken with the closing of the comers, tor it is here where 
leakage is usually discovered. 



332 



SHIPS' BOATS 



When the tank-makers understand that every buoyancy air- 
case has to be water-tested, it naturally makes them careful as 
to the quality of the joints. 

The width of the hook joints should not be less than § in. 




B 




] 











F G 

Y\Q, 191. Method of constructing metal buoyancy air-oases. 

Tanks must not exceed 4 ft. in length, and where they are 
more than 3 ft. 6 in. in length a divisional bulkhead should be 
fitted at the half-length for stiffening purposes. This is some- 
times done by inserting a skeleton bulkhead made of hardwood 
battens, properly secured by fore-and-aft stays to prevent 



CONSTRUCTION OF BUOYANCY ATE-CASES 333 

movement. jVn improved method is to fit a metal divieional 
bulkhead secured by small angle bigs and soldered to the sides of 
the air-casG. (See Figs. 191 f and g.) An alternative method ia 
to corrugate the sides, which appears to satisfy the requirements 
oi the wat«r teat, provided the depth of the tank ia within 
reasonable limits. 

The writer's experience has proved that 4 ft. is far too great 
a length for buoyancy-tanks. They cannot be inserted between 
the thwarts under the side benches, without making portable 
the sohd support under the thwart fitted in line with the tank 
cleading, which is considered very undesirable. The tanks have 
I be periodically inspected, and it is, therefore, necessary to 
make them easily removable ; three feet is considered to be the 
maximum length for general utility purposes. 

The material from which the buoyancy -tanks are made 
should be periodically inspected for surface defects^ and strips 
cut and tested for ductifity. 

The manufacturer's stamp must always be inserted on the 
yellow-metal aheeta, and the latter should occasionally be 
weighed to ascertain if they fulfil the requirements aa to weight 
and thickness, viz. not less than 18 ozs. to the square toot. 

There is more in this question of surface inspection than one 
would imagine. The boatbuilder or tank -maker has no guarantee 
from the metal merchant as to the quality of the material beyond 
the insertion of the trade stamp. It is the opinion of many 
builders that it would be preferable for the sheeta to be inspected 
and samples tested before the whole of the material is delivered. 

Defective tanks are a source of great danger to the boat. 
Zinc and galvanised iron are corujidered unsuitable for the purpose 
of air-cases or buoyant apparatus. 

Instances have occurred during the survey of old boats when 
taking out the buoyancy air-caaes for inspection, when it ha» 
been found that some of the tanks have become defective and 
leaky. 

The boat during the voyage has probably been flooded to 
keep the planking tight, with the result that the buoyancy 
tanks have become fidl of water. In course of time the defective 
joint has mated up, retaining the water inside the tank, destroying 
the purpose of the air -case, and endangering the stability of the 
boat. The necessity for water-testing each individual tarJi before 
delivery to the boatbuildeY ia, therefore, obvious. 

Metala which have been cold-worked are sometimes Uable 
to what ia termed " seaaon-crackifig," which only makes an 



334 



SfflPS' BOATS 



appearance after the material has been worked up into buoyant 
air-caeee, particularly when the sheets have been exposed 
heat or come into contact with some corroBive element. 

An interesting example of the defect recently came before the 
writer's notice. A set of yellow-metal tanks had paBsed through 
the test tank filled with wat«r ; the result of the test gave no 
evidence of leak^e, and a superficial inflpection showed no 
material defects. The tanks were expo.sed id the sun to dry, 
then placed in position behind the cleading in the lifeboat«,j 
Several weeks elapsed when the tanks were removed, and it 
then discovered that " season-cracking ' ' had developed, the tai 
were, therefore, useless for the purpose for which they 
intended. 

Several reaaona may account for the development. The test 
tank was exposed to the open air and adjacent to the roof of a 
building, where it was quite possible for water from the roof to 
find its way into the tank. In all probability there was acid in 
the water, and the pressure exerted on the buoyancy air-case 
during the test opened out the season-cracks, allowing the 
corrosive efiect of the water to complete the damage. 

Testa were taken on strips cut immediately in way of th< 
defects, which showed the material to be shghtly brittle, but th< 
metal was quite good in other parte. 

In the majority of cases of defects— the cratjking was started byj 
superficial corrosion, the attack of the corroding agent separatiiu[j 
the crystal grains of the surface layer, the result being veiy 
similar to a crack. 

A rough surface on the metal sheet immediately raises one' 
suspicion as to the quahty, and to a practical man the colour is »■' 
good indication and frnide. 

The weight of the completed buoyancy -tank runs out to about> 
5 lbs. per cub. ft. 

Precautions must be taken to keep the air-casee oft the rooves 
and other fastenings in the boat, by fitting rubbing strips attached 
to the timbers. The cases should also be placed in such a position 
aa to enRire the lifeboat floating on an even keel. They must also 
be secured in place to prevent lateral movement. 

A simple method tor providing means for testing the air-cases 
ia by filling with water a tank of sufficient size to take the largest 
air-caae. Insert one end of the case under a Icd^e or stop attached 
to the tank, and bring down the other end by hand pressure, so 
that the whole of the air-case is submerged. If there are any 
defects they will immediately show themselves by the appearanca. 



>at8^H 




CONSTRUCTION OF BUOYANCY AIR-CASES 335 

ot air bubblee. Turn the air-caae end for end and again inimeree. 
This nob only teats the air-case for water-tightneas, but alao for 
strength and rigidity. 

When the buoyancy-tank is completed it is thfl usual practice 
to insert a smalt tube and inflate the tank under air presaure, 
afterwards soldering up the hole. In pasaii^ the cases through 
the tank, the rounded surface sometimes becomes distorted ; the 
dodge to rectify this difficulty is to place the metal case in front 
of the stove, when the internal air becomes heated and expands, 
forcing the metal back to its original shape. If the air-cases are 
kept within reasonable dimcnaiona there should be no necessity 
for this practice. 

In some shipbuilding and boatbuilding yards, buoyancy- 
tanks are not only tested for air-tightneas, but are measured for 
capacity by displacement, the one operation serving the double 
purpose. 

The test-tank ia of rectangular shape, and the horizontal 
internal area is so arranged as to take the maximtmi permissible 
lei^^th of air-case, with a suitable breadtii, giving 12 sq. ft. A 
brass sliding scale, decimally divided, is attached vertically to the 
inside of the tank near the water-level. 

A wooden grating is suspended from a crane, upon which are 
placed iron weighte. These are lowered into the water. The 
zero mark on the scale is then placed at the new water-level, and 
the grating with the weights removed from the tank. 

The air-caae ia then placed in the water, and the weighted 
grating lowered until the air-case, grating and weights are com- 
pletely immersed. The reading on the scale at the new water-level 
will give the volume of the air-case in cubic feet. 

This method gives the actual cubic capacity of the air-case, 
and may result in a small saving of copper or yellow-metal in the 
large cases, as compared with those measured in the usual way. 

The operation of testing under these conditions takes con- 
siderable time, as the water after each immersion of the tank has 
to become perfectly still before the scale readings can be taken 
with any degree of accuracy ; consequently, the prevaiUng method 
is to simply immerse the air-case in a water tank for the airtight 
test, and measure it for cubic capacity by Simpson's Rule, 

The following is an example of the formula used, and is fairly 
accurate when applied to straight-sided tanks of ordinary form, 
but when the cases are curved as in nested boats, or of peculiar 
shape when placed in the ends of boats, this method is not reliable, 
and the actual capacity should be obtained by displacement. 



336 



SHIPS' BOATS 



Reference should be made to Fig. 192. 

Area of Section A = ^(a+ 46) 

D' 
Area of Section B = — (a + 46) 

6 



,, I £ . • area of Section A + area of Section B . 
Volume of air-casc = ^ X L 



I'f 



i 



j.._ 




Via. 102 



Fio. 193. 
^(otho<l of measuring buoyancy air-cases. 

The leiij^th must be taken from end-to-end sections, and not 
from tlio cdf^e of liook joint. (See Fig. 193.) 

Example. 
Section A =- D ^ IS', a = 10', 6 = -85' 

Section B -i)' == 1-2', a = -65', 6 = -55' 
L = -- 3-5' 



1-8 



Area of Section A ---- {I'O + 34) = •3(4-4) = 1-32 sq. ft. 
Area of Section B ■--- ^,- (-65 -h 2-2) = •2(2-85) = -57 sq. ft. 



1"32 + -57 „ . 
Volume of air-casc= — ., X Ao 



1 -89 -X 3-5 = 3-3 cub. ft. 

9 



^L an 



CONSTRUCTION OF BUOYANCY AIR-CASES 337 

Wooden aiT-cnses are not allowed to be inserted in tte life- 
boate of a vessel engaged in the ForeifSi Trade, but they were 
permitted in Home Trade vessels during the period of the war, if 
boatbuilders or shipbuilders wished it. 

There is a gceat amount of labour in building these air-cases 
to suit the form of boat and the required capacity. 

The construction of air-eases is practically a trade in itself, 
requiring an expert to fix suitable sizes for the particular boat 
to be built ; consequently, the demand for wooden eases is 
restricted. They are heavier than metal cases, and require a 
much greater length of time for conatruction. The material is 
cheaper, but, generally 
speaking, wooden cases 
are unsatisfactory. 

The Board of Trade 
have issued instructions 
for the construction of 
wooden air-cases. 

In the first place 
the material must be 
of very special quality 
and well seasoned, 
usually of yellow pine, 
3-ply wood, or other , 
suitable wood ; quite 
free from shakes and 
knots. Heartwood should be carefully avoided, owing to its 
tendency to spUt. 

The thickness of the sides, if not made from 3-ply wood, 
is not to be less than g- in. The ends are made of elm, or an 
equivalent hardwood, not less than I in, in thickness, with 
longitudinal stiSeners 1} in. by J in, of white or red pine fitted 
at the comers, to form the framework upon which to build the 
case. 

Laid over on the faying surfaces of the ends and longitudinal 
stiffcDers, are strips of hessian, coattxl with tar or marine gltie, t«i 
ensure a watertight joint. 

The inside surface of the top, sides and ends, are well coated 
with tar or marine glue, and secured together with brass or 
galvanised iron screws. 

The outside is coated with marine glue covered with hessian, 
and well ironed imtil the glue comes through the fabric. The 
air- case is then completed by a final coat of marine glue. 




338 SHIPS' BOATS 

They are fitted in the lifeboats in a similar way to the 
metal air-cases, and the usual precautions taken to ensure 
there is no movement after being placed in position behind the 
clcading. 

The regulations issued by the Board of Supervising Inspectors 
in the United States of America, relating to buoyancy air-cases, are 
of interest to British boatbuilders, and the following particulars 
are taken from the Edition of General Rules, dated April 8th 
1918, viz. :— 

'* All lifeboats contracted for after September 30th, 1912 
** shall have not more than 50 per cent, of the air-tank capacity 
" in the ends of the boat, and the remaining capacity shall be 
** located in the side tanks. 

" After June 20th 1912, the air- tanks of all lifeboats shall be 
*' entirely independent of the hull or other construction, and shall 
'' be of suitable non-corrosive material and of a capacity of not less 
" than 1*5 cubic feet for each person allowed in metallic boats, 
" and not less than 1 cubic foot for each person allowed in 
" wooden boats. Such air-tanks shall be firmly and securely 
'' fastened in tlic hull, and in such a manner as will allow them to 
** be temporarily removed, and in no case shall the tank be 
" punctured or opened for such fastenings. 

" The tops of such tanks shall be thoroughly protected by a 
** grating or platform, or by the thwarts or seats. Such air-tanks of 
" G cubic feet or less shall be constnicted of material of a thickness 
*' not le.ss than No. 22 B.W.G. ; from 6 cubic feet to and including 
** 15 cubic feet, of a thickness not less than No. 20 B.W.G. ; and 
" all air-tanks of more than 15 cubic feet capacity shall be of a 
** thickness not less than No. 18 B.W.G. 

*' All joints of air-tanks shall be properly double riveted 
** and tightly caulked or securely hook-jointed and efiiciently 
" soldered, or properly and securely welded, and such air-tanks 
** shall be located in such a manner as will permit the lifeboat 
''to be on as near an even keel as possible when flooded with 
•• water. 

** The cubical contents of air space of air-tank shall be stamped 
*• on the tank where same can be seen when air-tank is placed in 
the boat. 

Ml air-tanks shall be fitted with a connection of one half- 
'* inch outside diameter, for testing purposes. 

" Bt'fore any lifeboat is passed and accepted, the air-tanks 
*• thereof shall be tested in the presence of an inspector of this 
'' service, by an air pressure of not more than 1 lb. to the sqiLare 






I 



CONSTRUCTION OF BUOYANCY AIR-CASEK 339 

" iiich. At eacli aiibsoquent annual inspection, ot oftener if in 
" the opinion o£ the inspectora it ia necessary or desirable, the 
" inspectors shall satbfy themselves that the tanks are ot good 
" condition, but pressure need not be applied imlesa the inspectors 
" are in doubt regarding the efficiency of the tanks. 

" This doea not take from the inspectors the right and 
" authority to satisfy themselves at any time, either by examina- 
" tion or pressure, as to the condition of the tanks." 



'ARIOUS OLASSSS OF 

Wooden Lifeboats of Class Ia. — The buoyancy of a boat of 
this type is provided by watertight air^caaes, the total volume of 
which is to be at least equal to ten percent, of the cvJ»c capacity 
of the boat. 

Wooden Lifeboats of Class Ib. — The itU^Tuil buoyancy of a 
boat of this type is provided by watertight air-cases, the total 
volume of which is to be at least equal to TJ per cent, of the cubic 
capacity of the boat. 

K the external buoyancy is of cork, its volume id not to be 
less than thirty-three thousandths of the cubic capacity of the 
boat. 

Open Lifeboats of Class IIa. — ^A boat of this type is fitted with 
watertight air-casea for internal buoyancy, and usually with sohd 
cork [or external buoyancy, they must be at least equal to the 
following amounts : — 



Air-cases 

External buoyancy (if of cork) . 



1-5 cub. ft. 



for each person which the boat ia able to accommodate. 

Open Lifeboats of Hodifled Class IIa. — The dif!erence 

between thia type of boat and the Class IIa roainly consists in 
^^ diapcnsing with the outside buoyancy and increasing the internal 
^^ buoyancy, made up by metal air-cases, the volume of which is 
^H at least equal to 17 cub. ft. for each person which the boat is 
^H able to accommodate. 

^1 Steel Lifeboats of Classes Ia and Is.— In the case of a metal 
^H boat an addition should be made to the cubit; capacity of the 
^H internal buoyancy, by increasing the volume of the watertight 
^B air-cases, so as to give buoyancy equal to that of the wooden 
^H boat. 



340 SfflPS' BOATS 

The additional volume of air-cases required for metal lifeboats 
is obtained from the following formula : — 

V=.KW 

V => additional capacity in cubic feet. 

W =: the weijL^ht of the metal hull in cwts., exclusive of fittings, 

equipment, and air-cases. 
K = 175 when the mean weight of the air-cases is 7 lbs. or 

less per cub. ft. of capacity. 
K =: 2 when the mean weight of the air-cases is 14 lbs. per 

cub. ft. 

When tlie wei«^ht of the air-cases is between 7 and 14 lbs. per 
cub. ft. capacity, the value of K is found by interpolation. 

Wooden Motor Lifeboats, Classes Ia or Ib. — In fixing the 
volume of the internal buovancv, and, where fitted, the external 
buoyancy, regard must be paid to the difference between the 
weight of the motor and its accessories, and the weight of 
the additional persons which the boat could accommodate, if 
the motor and its accessories were removed. 

The Life-saving Appliances Rules are somewhat vague to the 
mind of the boatbuilder as to what is actually requied. The 
requirements can be made explicit by an example — 

Take a wooden motor boat of the following dimensions : — 

220'X70'X2'9". 
Capacity of boat measured by Simpson's Rule = 256 cub. ft. 

=> 25 persons. 
( 'apacity coefficient of form = '6. 
Diiuensious of motor and suitable space for working 

■•^ i-ry X 3-5' X 2-9' =- 45-68 cub. ft. 
which therefore displaces 4 persons (45'68 -r- 10). 

(a) Internal buoyancy required by boat capacity for a Class I a 
lifeboat =^ -,'o " ^ 25*5 cub. ft. 

(b) Internal buoyancy required for motor, etc. — 
Weight of motor and accessories estimated at 7*5 cwts. 
Buoyancy per cwt. (metal) = 1*75 

7-5 X 1-75 = 1313 cub. ft. 

(c) Buoyancy for persons displaced by motor, etc. — 
Weight of 4 persons displaced by motor and gear 

== 4 X 165 lbs. = 5-9 cwts. 



CONSTRUCTION . OF BUOYANCY AIR-CASES 341 

Buoyancy at 1 cub. ft. per person = '68 cub. ft. per cwt. 
Therefore, buoyancy displaced = '68 X 5*94 => 4 cub. ft. 

Summary. 

Buoyancy required at (a) = 25-5 cub. ft. 

(6) =13;13 „ 

Total 38-63 

Deduct buoyancy displaced at (c) = 4*00 

34-63 



it 
>> 

if 



Total number of persons given by capacity rule = 25. 
Number of persons displaced by motor, etc. = 4. 

If seating accommodation is provided for 21 persons, then the 
buoyancy air-cases must be 34*63 cub. ft. 

If seating accommodation is provided for only 17 persons, 
then the buoyancy air-cases must be 34-63—4-0 (4 persons less 
@ 1 cub. ft. per person) 

=• 30-63 cub. ft. 

Note. — If the motor boat is constructed of steel then the 
buoyancy air-cases must be increased in volume so as to give 
buoyancy to the steel hull equal to that of a wooden boat. 



PART VJl 



SECTION A.— EQUIPMENT OF BOATS 
There has been frequent complainta when inquiries have been 
held in regard to various casualty cases, as to the inefficiency or 
the absence of some details of the equipment in the lifeboats. 

The Life-saving Appliances Rules make full provision for all 
reasonable emergencies which a lifeboat is hkely to encounter 
and it largely depends upon the ship's officers as to whether this 
equipment is kept in satisfactory condition and always remains 
in an accessible position. 

Adequate provision should be made in the boats to suitably 
stow the various details of equipment, to enable them to remain 
in a serviceable condition and be protected from the weather. 
A simple plan is to build lockers into the ends of the boat, having 
portable platforms adequately supported above the keelson, and 
protected at the front with strong hinged doors fitted with 
suitable slip bolts. 

The statutory rules do not at present demand the fitting of 
these lockers, but the experience of our sailors who were cut 
adrift from their vessels during the recent submarine warfare, 
and exposed for several days, and even weeks, in an open boat, 
should be sufficient evidence of the necessity for making the 
provision referred to. 

■ "Where competition is keen among so large a number of boat- 
builders, it is e^ntial to stipulate every detailed requirement, 
and not to leave these matters to the persuasive powers of the 
surveyor or to the common sense of the builder. The demands 
should be clean cut and definite, which will ensure satisfaction 
to all concerned. 

The details of eqiupment depend on the classification of the 
vejisel. That is to say, the trade of the vessel has a direct bearing 
on the requirements ft)r providing the boats with those essentials 
which will enable the crew and passengers, in case of disaster, 
to be succoured until the arrival of assistance ; it would, therefore. 



EQUIPMENT OF BOATS 343 

be advantageous to give in detail tlie full ecjuipiuent which is 
required by the Life-saving Appliances Rules, for the various 
clasacs of vessels. 

For a dettcription of the various classes of vessels, reference 
should be made to Section A of Part II., as it seems unueceasary 
to repeat the explanation. 



EQOIPHBNT OF BOATS FOR FOREIGN-GOING VESSELS. 

Classes I., II., III., and IV. 

Every boat which forms part of the statutory equipment of a 
vessel should be supplied with the following details, viz. : — 

1. A full single-banked complement of oara, two spare oars, 
and a steering oar; {See Table XXII,) 

2. Two plugs for each plug hole, attached to the boat 
with lanyards or chains. These are not required where proper 
automatic valves are fitted. 

3. One set and a half of thole pins or cmtches attached to the 
boat by sound lanyards, 

i. A sea anchor. 

5. A balpr with lanyard attached, which should be of sufficient 
size, and made suitable for baling, the upper diameter not being 
less than 8 in. 

6. A galvanised iron bucket to hold 2 gallons, with lanyard 
attached. 

7. A painter, not less than 20 fathoms in length. 

8. A nidder and tiller, or yoke and yoke lines. The rudder 
and tiller t^i have lanyards of sufficient length to enable them to be 
securely attached to the boat. 

9. A boat hook of convenient length, and strong enough for the 
purpose requited. 

10. A vessel capable of holding one quart of fresh water for 
each person that the boat is deemed fit to carry. This vessel 
must be kept filled, and provided with a suitable dipper attached 
to a lanyard. Two galvanised iron tanks or breakers arc required 
in the large boats, to hold the specified quantity of water, the 

I smaller size being more convenient for sttiwage and handling 
and less likely to be damaged. 
11. Two hatchets, attached to the boat by a lanyard and 
stowed one at each end of the boat, ready for cutting the falls 
or painter if necessary. 
12. A life-line securely becketted round the outside of the 



344 SfflPS' BOATS 

boat, secured to life-rings clenched to the timbers not more than 
2 ft. apart, having loops of sufficient depth that will always remain 
a few inches above the water-line. 

13. An efficient lantern trimmed with oil in its receiver, 
sufficient to bum eight hours, and capable of burning in a strong 
wind. This should be of brass or copper frame, and of a size 
that will conveniently fit in the galvanised bucket referred to 
in item 0. 

14. A mast or masts, not more than two-thirds the length of 
the boat, with at least one good sail and proper gear for each.' 
(See Table XIV. and Section B, Part VII.) 

This rc(iuirement does not apply to an approved motor boat. 

15. A licjuid compass. 

1(). An airtight case, ccmtainifig two pounds of biscuits for 
each person for whom the boat is approved. 

17. One galhm of vegetable or animal oil. 

18. A vessel of api)r()ved pattern for distributing the oil on the 
water in rough weatlier. This vessel must be capable of being 
attached to the sea-anchor. 

19. One dozen self-igniting red lights in a watertight tin. 

20. A box of suitable matches in a watertight tin. 

The above details are to be kept so as to be at all times fit 
and n^adv for use. 



EQUIPMENT OF BOATS FOR HOME TRADE VESSELS. 

Classes I., II., III., IV. and V. 

Every boat which forms part of the statutory equipment of a 
ve^jsel must be siij)j)lie(l with the details as shown in the foregoing 
list for forcign-uoiii.t: v(\ss(»ls, with exception of items 14 and 16. 

EQUIPMENT OF BOATS FOR HOME TRADE VESSELS. 

Classes VI., VII., X., and XI. 

Full details to be, supplied as shown for foreign-going 
vessels, excei)t items 14, 15. 1(), 17, 18, 19 and 20. 

EQUIPMENT OF BOATS FOR HOME TRADE VESSELS. 

Classes VIII. and XII. 

Full details to be supplied as shown for foreign-going 
vessels, except items 4, G, 10, 14, 15, IG, 17, 18, 19 and 20. 



EQUIPMENT OF BOATS 



EQUIPMENT OF BOATS FOB HOME TRADE VESSELS. 
Class IX. 

Full details to be supplied as shown for foreign-going 
vessels except items 4, 6, 10, IS, 14, 15, 16, 17, 18, 19, and 20. 

The full equipment of boats for vesaela of Class IX. would 
therefore be — 

- [a] A full single-banked complement of oara, two spare oars, 
and a steering oar. 

(fe) Two plugs for each plughole, and attached to the boat by 
lanyards or chains. 

(c) One set and a. half of thole pina or cnitches. 

(d) A baler with lanyard attached. 

(e) A painter of sufficient length. 

(/) A rudder and tiller, or yoke and yoke Unes, 

ig) A boat hook. 

(h) Two hatchets, with lanyard attached. (See note below.) 

(i) With a Lne securely becketted around the outside of the 
boat. 

Note. — Where boats of vessels, Classes VIII., IX. and XII. 
are put into the water by hand, and not by means of davits or 
other mechanical appliances, they need not be provided with 
hatchets (item 11). 

Class III. boats, which form part of the statutory equipment 
of a vessel, are provided with the same details as a lifeboat ; the 
only difference between this type of boat and the lifeboat of 
Claas Ia is that the former is not fitted with buoyancy air-cases. 

The Board of Trade may exempt from the requirement to 
carry masts, sails, and compasses, a proportion of the boats of 
ships which carry passengers in the North Atlantic and are 
equipped with wireless telegraphy. 

To provide a quick and ready means of identifj-ing the boats 
which are fully equipped on such a vessel, it is usual to paint a 
broad red band, at least 3 in. in breadth, around the outside of 
the boat under the rudder. 

The whole of the equipment provided must be of good quality 
and efficient for the purpose intended. 

Unless periodica! inspection is made, and the lockers kept 
free from dirt and water, the details of equipment will very 
quickly deteriorate, it is therefore the duty of the ship's officers to 
see that all the gear is in proper condition and stowed in all the 
boats, and carefully inspected at each periodical boat drill. 



346 SHIPS' BOATS 

Tabic XXII. on p. 347, gives a detailed statement showing 
the length of oars required for boats of certain length. The oars 
should be of straight-grained ash ; in good class boats the 
blades are copper tipped and leather bound in way of crutches 
or thole pins. The lengths vary to suit the particular size of 
boat, the position of the thwart, and the height of the gunwale 
above water. 

The position of the crutches should be so arranged that the 
boat can be pulled with a greater number of oars on one side, to 
suit the conditions of wind or stress of weather. This is the 
reason why the crutch plates should be double-banked in the 
smaller boats. 

In this connection, it facilitates easy removal, if the crutches 
are secured to the boat by lanyards instead of chain, in order to 
allow them to be placed in the most suitable positions for rowing. 

The limit in length for a steering oar is 16 ft. ; it is painted a 
distinctive colour so as to be easily recognised, and is usually 
about 1 ft. greater in length than the longest rowing oar supplied 
to the boat. The blade should be wider than that of the ordinary 
pulling oar. 

The simplest, most efficient, and one of the oldest methods of 
holding the steering oar is by fitting a wire grommet served over 
with marlin stuff or spun yam. This grommet is seized behind 
the ring bolt and a good security made. The length of the 
grommet should be such that the blade of the steering oar can 
easily be inserted and the oar used on either side of the stempost. 
To protect the capping of the gimwale, rubbing pieces well 
rounded, should be fitted on each side of the stempost for about 
15 in. from the sternpost head, secured by screws to the gimwale. 
It is mucli easier to renew the loibbing pieces than repair the 
upper strake or gunwale. Details of this method is shown in 
Fig. 103. 

In a square-sterned boat, a rowlock is usually cut in the 
transom for the purpose of sculling. The steering grommet is 
seized behind the ring bolt in the usual way, the grommet and 
rowlock combined forming an efficient means for supporting the 
steering oar. 

The sea anchor nuist be ccmstructed of good quality canvas. 
Keen competition among ship chandlers, without a universal 
specification or definite standard to work to, has been responsible 
for many inferior fittings being supphed for the boat's equipment, 
which includes the sea anchor, the purpose of which is to allow 
the boat to ride stcadilv in a seaway. The sea anchor acts as a 



EQUIPMENT OF BOATS 



347 



drag, and is used in association with the oil distributor, which is 
supposed to break down the roughness of the wave surface. 



TABLE XXII. 

Pabttoulars of Thwarts, Cbutohes, and Oabs, fob Boats of Classes Ia, 

Ib and III. 



Length of 

boat in 

feet. 



16 



17 & 18 
19&20 



21, 22. 
&23 

24 



25 & 26 



27 



28 



29 & 30 



Number 

of 
thwartfl. 



6 
6 
6 



Number of 
crutch plates. 



Single- bank I 

No. I Thwart. 

Double- bank 

2nd and 3rd 

Thwarts. 

Total 5. 

Ditto. 



Single- bank 

No. 1 Thwart. 

Donble-bank 

elsewhere. 

Total 7. 

Ditto. 



Ditto. 



Ditto. 
Total 9. 

Ditto. 



Ditto. 



Double-bank 

Five Thwarts. 

Total 10. 



Total No. 
of crutches, 
including 
spare. 



6 







6 



6 
6 
6 
6 
8 
8 



Total No. 
of rowing 

oars 

including 

spare. 



5 



6 



6 



6 



6 



6 



8 



8 



Length of Length of 

rowing steering 

oars in oar in 

feet. feet. 



10 



2 @ 10 

3 @ 12 

2 @ 11 

4 @ 12 



2 @ 11 
4 @ 13 

2 @ 12 
4 @ 14 

2 @ 12 

4 @ 14 

2 @ 13 

4 @ 14 

2 @13 
6 @ 14 

2 @ 13 
6 @ 15 



12 



13 



13 



14 



15 



15 



16 



16 



16 



Fig. 195 A shows one type of anchor, circular in section, not less 
than 24 in. in diameter, made up from canvas, well strengthened 
by hemp rope ; attached to the sea anchor is a stout rope trailer 
and tripping Une, 20 fathoms in length. The tripping line is used 
to turn the tail of the anchor towards the boat and enable it 



348 



SHIPS' BOATS 



to be drawii on board, The hoop aroiind which the coitvas 
secured should be of substantial section and made suitable for ths 
purpose intended. This pattern of anchor is an awkward shape 
for stowing in the lockers, and very quickly deteriorates when 
lying at the bottom of the boat. Fig. 195 b illustrat«s another 
pattern which is eaeily rolled up and stowed away, but it ia 
doubtful whether it possesses any advantage in actual use over 
the one previously deacribed. It consists of a piece of stout 
canvas 2 ft. 10 in. square, with a wood float 3 ft. 3 in. in length 
and 3 in. by 2J in. in section at one end, and an iron bar at the 
other. The feature of the latter is to keep the canvas under 
water, as in conjunction with the trailer and tripping Una 
attached to the canvas, it makes a 8coop and provides th« 
necessary resistance or drag. 

The oil-distributing apparatus should be capable of distributing 
oil evenly and gradually on the surface of the water ; it is usually 
attached to the sea anchor. The common fitting supplied is an 
ordinary thin canvas bag with a narrow neidt, which is a most 
unsatisfactory and a useless article for the purpose required. A 
better class of distributer is shown in Fig. 196. It consists of & 
stout canvas body with a metal spigot securely attached to the 
former, having a screwed cap which can be adjusted to allow the 
oil to be distributed in suitable quantity. Other patterns are 
on the market, hut they very rarely become a part of the equip- 
ment, because the cheaper article appears to satisfy the present 
requirements. 

The painter should be not less than 20 fathoms in length. It 
is a great advantage to have two of these in each boat ; during 
the recent submarine warfare it was insisted upon as an essential 
part of the equipment, one being fitted with a strop and toggle, 
and the end led forward and kept belayed to a cleat or othei 
suitable fitting fixed on the deck or bulwark. 

The purpose of this painter is to allow the boat to be lowered ' 
before the vessel has come to rest, and to enable the seamen to 
reheve the boat from the falls. 

This provision particularly applies to lifeboats stowed oa 
the poop, or near the after end of the ship ; the cleats shouldi 
be so placed that boats when lowered and freed from the tackle^, 
with the ship light, can be held by the painter clear of the coiintaE^ 
and propellers. 

The remaining, or second painter, should be neatly coiled 
stowed in the boat, ready for use if required after launching. 

If only one painter ia supplied, and it becomes ni 



I 
I 



EQUIPMENT OF BOATS 



349 




rmpptAfc 

UNE 



- ELEVATION - 




■ PLAN - 

Fia. 195 A and b. — IX^tails of sea 
anchor. 




B 



CANVAS 
2-10 % 2.IO 



IRON ROD 





MerAL Af£C/( 



SlS£Y£ 





CAP 



r\ m 






Fio. 196.— -Details of oil distributer. 



SOO SHIPS' BOATS 

Ut cut tlic li'iat aflrift from the veuel with the hatchet, the bcwt 
will li'; li;ft without meatu for towing in case of neccBsity, tinlt<w; 
the m-ji unchor trailer i^ used for the pnipose. 




'I'lii- ]iriivisiiiii i>f siiiluhli' rrxsrls fur holiliiif) fresh tmter is of 
niiiMi>l('i'iili]t> itii|>ni'(itiit't'. Ilroukocs or bairicoeii are usually 
uujipliiHl. 'I'wo in uuuibev uro placed in each boat, conta' 



EQUIPMENT OF BOATS 



351 



total quantity of water equal to an allowance of one quart for 
each person the boat is certified to carry, 

A gallon of distilled water weighs 10 lbs., ao that the capacity 
of the breaker can be checked by ite weight when filled. 

New breakers should be filled immediately they are euppUed 
to a boat, in order that the wood may absorb and become water- 
tight. They should be neatly stowed in cradles on each side of 
the keelson, clear of the lower seats, and lashed to eye-plates to 
prevent them being lost overboard. Fig. 197 d illustrates the 
method of stowing. 

The dippers ate attached to the breakers and weighted so as 
to allow the mouth to get below the surface of the water. The 
mateiial must be of copper or zinc, and tinned on the inside. 
Tin dippers arc condemned as a source of danger, and quickly 




Fill. Vit. — Jli'thod uf fitting two biscuit tanks uoder one thwart. 

ruat when exposed to the sea atmosphere. Particular care should 
always be taken to see that the dippers will enter the plughole of 
the breakers without difficulty. 

Gaivani.'^cd iron tanks are considered preferable to wooden 
breakei-s. The fittings connected with them must be of metal, 
and not of cast iron, to prevent rusting. 

Biscuit Cases. — Airtight metal tanks are fitted in the boat to 
c()ntain 2 lbs. of biacuita for each person the boat is certified to 
carry. 

No single tank should contain more than from 50 to 56 lbs. of 
biscuits, so that if a boat is certified to carry 29 persons, two 
separate tanks nmst be provided. 

In a lifeboat with five thwarts, and where the mast is stepped 
on the second thwart, the two biscuit tanks can he fitted side by 
side under the third thwart, and secured as shown in Fig. 198, 
but in lifeboats fitted with si^ thwarte, the biscuit tanks can be 



352 



SmPS' BOATS 




iDastzsted 



m^Mml U, Heparate thwarte, if considered 

ViuU'TtinUt metal ocrcw caps, not less f k 
yhmUl \„. f.ttwl U> the biscuit tanks, which.!!^^ ^ ™ di«neter, 
tr. B I..W a p.,rw.n t., place his arm inside faT^ **''?* «oagh 
(.f the tHiikx. ^"®' *<> the remotttt con^ 

A key or levc;r is suppHed and attached to tl.» k_ , 
or eham, .,r .,,,enin« the brass cap, unless Sel-^T*- ^^ ^^^ 
with the lever attached. ™® tatter is so fonned 

The „„iteriul Hhould be of galvanised sheet im ^ 

£^»5*rr "' anrabl^ and 




mr. 

TANK 



I 



- ELEVATION ^ 




Km. I!M». .MrtlHMl of jiiiin^r Hinglc biscuit tank under thwart 

of Htron;', Mcantlin«;. TIk* usual size of sheet is 6 ft X 3 ft r ri ^-u 
Miirknrss viiiirs from 20 to 22 W.G. * *' ^ ^^® 

Kor Mic purpose of socuriiijr a satisfactory cubic capacit 
fiirlor, to pinihlc a lank to ho of sufTicient volume to contam th^ 
nM|uinMl amount of l>is('uit.s, the writer secured typical sizes f 
slii|)s' hiscuits ami foinul the volume taken up by one poiind 
in IIm' followin;; manntM* :-- ' 

12 in numlxM-, hiscuit^s ((/ \\V' diameter = 1 lb. 

Dimousions for 1 Ih. lU" X 3.1" X GJ" = 76-5 cub. in. 

8 in numher, l)isruits ((/ '1|" diamet^^r = IJ lbs. 

Dimensions for \\ lhs.r_-li"x 41" x4i"=76-7 cub. in. 

7(r7x 1^>^ 722 cub. in. for lib. 
17 



EQUIPMENT OF BOATS 



353 



^ The basis for the eapacitv of a biscuit tank is therefore taken 
' as 100 cub. in. = 1 lb. ; 1 cub. ft. (1728 cub, in.) = 17^ lbs. 

It then becomes an easy matter to make a tank that will be 
larfje enough to take the required amount of biacuita, provided 
wc know tliB number of persons the boat is supposed to carry, 
and the depth available between the top of the keelson and the 
underside of the thwart. 

The following iuiorraation will, therefore, be useful in pro- 
vidinj; biscuit tanks for lifeboats of Classes Ia and In. and boats 
of Class III. 

TABLE XX] 11. 

DlBTiJfCB BFTWRRN BoTTOH OF ThWAHT AND ToP OI> KlELSOS, IH LirEBOATS 

or Classes Ia and Ib, ahd Boats or Ciabs III., ron the Acoohuooa- 
■nos at BiscitiT Tanks. 



DlD,eiwloii^ of l«)iit. 


No. 01 
l«r«uB. 


So. o( Ibg. 

ol bbcnlta. 


Oeptli kvailiMe 
lor blwult 


Single biMuit tank in each boat :— 
l6-0x575'x2-3' 
18-0'xfi-2fl'x24' 
20-0' X 0*78' X 26' 
22-0-x7-2a'xa-76' 


11 
ai 

2fi 


24 
32 
42 

52 


1'2* 

i'3r 

1-6- 


Two bisoDit tanka in esch boat :— 
2*0'y7G'x30' 
26fl'x8-0'x3-25' 
280' X 8-5' X 36' 


32 
40 

60 


04 
80 
100 


■:-i; 


Three biioait tanks in each boat :— 
3O0'x90'x3-75' 


00 


120 


2 3J- 



Compass. — The compass must be in accordance with handbill 
No. 377, issued bv the Board of Trade m July, 1916. The dry 
card compass has been discarded as a useless piece of equipment. 
Proper liquid compasses must now be provided and fitted in a 
brass binnacle, or in a suitable wooden box. The former are 
much t*i be preferred. 

Efficient accommodation should be made for the reception of 
the compass, that it may be protected from the weather and be 
in such a position from which the coxswain can steer the boat 
without difficulty. The usual plan is to secure a small box under 
the after thwart immediately in front of the stem-sheets, with 
a hinged front. The base of the binnacle must be secured to a 
wooden slide to aUow the compass to be withdrawn for the 

2 A 



354 SfflPS' BOATS 

purpose of trirnming the lamp. Such an anangemeiit is 
illustrated in Fig. 197 E. 

The internal size of the compass box will varr accoiding to 
the pattern of compass, but the following dimensions will usually 
accommodate most of the designs : — 

10 in. fore and aft, by 14 in. depth, by 13 in. athwartship. 

Ridge Spars are usually fitted to each boat of Classes Ia, Ib, and 
III., resting on the stem and stempost heads, supported by an 
upright from the keelson at the centre, and two struts from the 
gunwale. The purpose of the strut is to take the canvas or 
portable wooden covers which protect the interior of the boats 
from the weather. 

The common practice is to fit the canvas cover in one piece, 
secured with lashings through eyelets to solid brass knobs fixed 
to the imderside of the rubbers. 

It has often been suggested to the writer by ships' officers, 
that the canvas cover could be lapped and laced at the centre, 
and so arranged that when the boat was lowered into the water 
the cover would be retained, and secured by a lashing below the 
gunwale, so as to give the proper freedom for the manipulation 
of the oars. 

This scheme would allow the use of the canvas cover as a 
protection to the passengers using the side seats, and judging from 
the experience of those who were unfortunate enough to spend 
several nights at sea in an open boat, as a result of their vessel 
being torpedoed at sea during the recent war, the suggestion is 
worth considering. 

Hand Pump, — Every boat above 22 ft. in length could, with 
advantage, be fitted with a small pump for quickly clearing the 
bil^ci of water. The use of one small bailer has very httle effect 
in keeping down large volumes of water coming over the side 
(luring stress of weather. 

Whore vcHsels entered the war zone, the United States Steam- 
boat Inspection Service insisted on boats being fitted with a 
han(l-])uinp, having a plunger of not less than 2 in. in diameter, and 
a discharge pipe of sufficient length to reach clear of the boat's 
sido. 

General Ite^narks, — After reading through this section on the 
subject of equipment, one will naturally come to the conclusion 
that a lifeboat has a considerable portion of its capacity taken up 
with essential details. This fact should be carefully considered 
when the number of persons are being allotted to a particular 
boat. 




EQUIPMENT OF BOATS 355 

Some readers perhaps Lave seen the mffenioua arrangement 
placed in lifeboats, where a metal tank is fitted under the after 
thwart inunediatety in front of the stem-sheets, which is a 
self-contained store in miniature proportions, divided into three 
sections, an oil tank on one side, and a cupboard on the other. 
In the centre is an oil stove connected to tlie oil tank. Carried 
in the cupboard are, condensed milk, meat juice, brandy, a kettle, 
and other apparatus. Every convenience is thus provided for 
making hot drinks. 

This provision is worthy of consideration, when passengers 
ai'u often taken unwell, or wounded persons are being carried on 
boaid. 

To provide contact between one boat and another, a helio- 
graph for signallinf5 by day, an electric torch for use at night, 
and a box containing medical comforts, are very necessary portions 
foi inclusion in the equipment, but up to the present date the 
regulations do not require these fittings to be supplied, 

In addition to the statutory requirements of the British Board 
of Trade, the United States Steamboat Inspection Service ask 
for a canvas bag to be carried, containing sailmaker's palm and 
needles, sail twine, marline and marline spike. The food, or 
provisions required to be carried in lifeboats, may be hard bread 
or the " United States Array emergency ration." Food which 
produces unusual or immoderate thirst, such as corned beet, salt 
fish, etc., is not allowed imder any circumstances, as lifeboat 
provisions, 

When hard bread only is carried in the lifeboat, there must be 
provided, in addition thereto, at least ten United States Army 
Emergency Rations. The latter is prepared in accordance vntii 
the following formula : 45'45 per cent, chocolate liquor, 7'27 per 
cent, nucleo-casin, 7'27 per cent, malted milk, 14o5 per cent, 
^g albumen, 2182 per cent, powdered cane sugar, and 364 per 
cent, cocoa butter. Each ration weighs 8 ozs. net, and is put 
up in three cakes of equal size. Each cake is wrapped in tinfoil, 
and all three enclosed in a hermetically-seated, round-cornered 
tin, with key-tipening attachment. The formula thus described 
is printed on the container together with the name and address 
of the manufacturer. 

Dimemmis of each boat must be plainly cut in on the stem or 
the upper strake ; the former is considered preferable. The size 
of the figures being at least \ in. in depth. The dimensions 
required are the length, breadth, depth, and the number of 
persons the boat is certified to carry, and these must be so 



356 



SmPS' BOATS 



CA^y^s co^r^ 



placed as to look inboard. The number of persons is also cut 
in on the opposite side of stem. 

Each boat must be distinctly niunbered in figures about 
2^ to 3 in. in depth. The usual procedure is to paint tibese 
numbers in clear type to enable the boat to be readily identified. 
Starboard boats are given odd numbers, and those on the 
port side are marked with even numbers. The foremost boats 
are, therefore, numbered one and two respectively. 

The British Board of Trade issue a Life-saving Appliance 
Certificate (S. 123), on which is indicated the position and number 

of the whole of ^e boats which form 
part of the statutory equipment of 
the vessel, it is an advants^e to the 
surveyor if the identification number, 
which is placed by the boatbuilder on 
the keel immediately it is laid, is also 
inserted on the certificate, together 
with the date of construction, and 
the name of the boatbuilder. This 
information enables the boat to be 
traced, and forms a guide to the in- 
spector when making a p^odical 
survey. Fig. 200 indicates how the 
dimensions are placed on the stem of 
a boat which is situated on the port 
side forward, the dimensions, there- 
fore, appearing on the starboard side 
of the boat. 

The measurement of the capacity 
of a lifeboat has to be carefully con- 
sidered with reference to the amount 
of equipment which has to be stowed. 
It is useless to designate a boat as being able to accommodate 
a number of persons, given by the approved factor or irnit of 
capacity, without adjusting the seating arrangements in con- 
jimction with the various details of equipment. This difficulty 
particularly applies to the smaller boats. 

As a general rule, sufficient care is not exercised by the ship- 
builder to place the gear in its proper stowing position, at the final 
inspection of the life-saving^appliances, immediately before the 
vessel is delivered over to the shipowners, with the inevitable 
consequence that when the boat-s are required on service, various 
details are missing. 




Fig. 200. 




SECTION B.^AILS 

RegulatioiiB alfectlng Sails. — Boats which form part of the 
statutory e<jiiipment of all classes of foreign-goii^ veaaela, must 
be provided with a maat or masto, and at least one good sail, and 
proper gear for each. 

This provision dues not apply to an approved motor boat, or 
to boats whieh are carried on ships solely enjiaged in the Home 
Trade. 

In a ship which carries passengers in the North Atlantic, and 
is eqiiipped with wireless telej^raphy, masta and aaiU need only 
be provided in four of the boats, but these boats must be marked 
so as to distinguisb them from other boats, by means of a red 
band 3 in. wide, painted round the outside of the boat 
immediately below the sheer strake. 

Mast« must not be more than two-thirds the length of the boat, 
and the sails should be of j;ood quality duck of suitable size, e.g. 
a 28-ft. boat should have not less than 150 sq. ft. of sail area, 
other boats having areas of similar proportions. 

Each sail should be fitted for reefing. 

The boats must have sufficient stability, when in their fully 
loaded condition, to enable them to cany a aufiicient spread of 
sail in a fresh breeze. 

Propelling Force of Wind. — The force of wind which is exerted 
on the sails of a boat in order to pr6pel her forward, is not wholly 
effective in moviii[; her in the same direction as the keel, except 
when the wind is blowing immediately behind the boat. 

When sailing a boat to windward, the wind force isdirected on 
the sails in an oblique direction. One portion of that force drives 
the boat ahead, and another drives it to leeward. What we have 
to discover is the percentage of the wind force which is effective 
ill propelling the boat forward. 

The explanation can be made clearer by graphically setting 
t'ut the forces, as indicated in Fig. 201. 

Assume KK to be the centre-line of boat and representing 
the keel. 

Make PS to show the direction and force of the wind. 

Resolve this force into two components by the application 
of the principle of the parallelogram of forces, and we then have 
one component NS or PC acting along the surface of the sail 
which produces no effective forward motion to the boat. The 
iither component OS or PN is acting at right angles to the plane 



x> 



.SHIPS BOATS 



AwriiU'j: of tii#; -ail. k»5-iilv»> th*: f'/rc* PX ini»> rwo oj 

an/J w«: j^ii'Mtf: x}i('. htrf*: PK. which U th<? m<A£c:r^ »>t liie fff^tttm 

f/^iw'rr /irivinir th^: ho;^t <iheafi. the lin<^ ot Acti<^ bian;Z pArallei 

Th'r ot.h#:r com[>*irient KX U the measure of the fore?? vhidi is 
in op'jration t'-f»rliri'^' t/i driv*^ the hK>at to leeward, i-if. moving the 
^fff(tt 'inU'WfiVA awav from the wind. 

Th'r iin/J^rrwat^ir form of the bf>at. the depth of the keel, and 
tJi'r jfffMtlion of fhe Hfidn, all have a direct influence in ci>xmteraetin2 
y\\t'. t'tttul of th<' forr<; driviri;: the hK>at to leeward. 

'{]}*' Tf"\i*.UiU('ii oi the h-ninh and lon^ritudinal shape of the boat 
to \n'. driv^Ti in ihf. dir^frtion RX is comparatively greater than 
till- ft'M'Jiuiff. ofT<Twl by the breadth to the forward propelling 



X 



*'/ 



ftlMO PPeSSt^ffE 




i-K. ;!0I. U\,\\t,r\\\\\ kA wind forcc?i acting on aail 



lofM' l'|{. iu\\.ri\\\\'\\\\\ tlic. boat is moved by the wind in a 
<ln<'(lion |>ii.rnll('l t^> the. k<;«'l. 

Ifi'li-i Mii.i roiKiitinn of wind pressure, the leeward force is 
rofnhiiillv <-\«-ilin;' an inlliMMice on tin; boat, tending to drive the 
boiil. nil lii'i roiii.'.r. but tin* proprlliiij^ force, which is sometimes 
M-b'iH-(l to JIM till- lorcr prodnc'in;: angular velocity, will be in 
i^xri-.'.,! ol till' liM'WJud lone provicb'd the mast and sails are placed 
\\\ tlicn «'ori«>(-t poi^itions. 

Fowur lo Carry Sail. It is considt'red that sufl&cient informa- 
tion Ini.i jibi'jMJy JH-cn ^'ivrn in Section C, Part II., to enable the 
rrjnl'T to inMlrrstiuHJ tlir various (polities of a boat in order that 
MJM*. will n*niain in a st.ablr. condition when in a seaway. There 
is a fnrt-lMT jpudity which a boat must possess to be an effective 
lilcMiivin;.' a|>|>liancc, should sIm» b(^ within a reasonable distance 
from hind, and h-ft U^ her own resources : 'that (piality is termed 
*' the power to carry sail." 

Centre of EfTort. -One of the lirst consideratiims is the position 
of the •* centre of elTort " and the " centre of lateral resistance." 



SAILS 



359 



The centre of effort (CE) is really the centre of gravity of 
the sail area., or the point at which the resultant of the wind 
forces spread over the sail, is assumed to act ; or in other words, 
the centre of effort is the position where the accumulated effort 
of the wind is assumed to be centred or controlled. 

The sails generally used on ships' boats are the standing or 
dipping lug and the jib. 

The " centre of effort " of a sail plan is found as follows : — 

Reference must be made to Fig. 202. 



/ CE.NT/t£0r£f-FO/fT Or JIB 

z ccN 7P£ oTE^roffr or LUG 

3 CENTftE or£ffOPr Of fUlL 
SAIL ARCfk 




Fig. 202.— Method of finding the centre of effort of sail area. 

Take the jib of triangular shape, bisect foot FG, and draw a 
line to E. 

Bisect the luff FE and draw a line to G. 

The intersections of these two lines within the triangle EFG 
will be the centre of effort of the jib. 

We next deal with the lug-sail. 

The same principle of working is used with the dipping as in a 
standing lug. 

Draw a diagonal line from throat at B to the clew at D, thus 
dividing the sail into two triangular portions. 

Proceed as in the case of the jib to find the centre of gravity 



360 SHIPS' BOATS 

of each triangle. Join these two points, and divide the line 
inversely as the sail areas, to give the centre of effort of the 
standing lug-sail. 

In the case where a boat is fitted with a standing lug and jib, 
as illustrated in Fig. 202, it is necessary to find the area of each 
individual sail, and the position of the "centre of effort," relative 
to th^ " centre of lateral resistancey" and the stem or middle of 
length of boat. The procedure is as follows : — 

(a) Multiply the area of the jib by the distance between its 
centre of effort and the centre of lateral resistance. 

(b) Repeat the operation for the lug sail. 

If we add together the result of (a) and (6) we obtain the total 
vertical moment, and dividing this quantity by the total sail 
area, we obtain the final position of the centre of effort of the 
whole sail area, relative to the centre of lateral resistance. 

To obtain the fore-and-aft position of the centre of effort, we 
take moments about a vertical line at the mid-length of the boat, 
and proceed in the same way as we did with the vertical moments, 
dividing the total moment by the total sail area. Where the 
horizontal line drawn through the centre of effort in its relation 
to the centre of lateral resistance, intersects the vertical line 
drawn through its position relative to mid-length, centre of mast, 
or front of stem, whichever is used, that point of intersection 
is the centre of effort of the whole sail area. 

An example wiU simplify the explanation. Take the sail areas 
for a 28-ft. Class Ia hfeboat, viz. : 

37 sq. ft. for the jib, and 

1G3 sq. ft. for the standing lug. 



Q„„ Area In Distance between Vertical ' ^ri*?nrvL^«ir^'* Horizontal 

"*"• sq. ft. CE and CLR. moments, i mid-length niomentt*. 



Jib 37 8-7 ft. 321-9 93 ft. ' .3441 

Lug 1()3 0-5 ft. 1548-5 -65 ft. 89G5 



Total area = 200 sq. ft. 
Total vertical moment = 1870*4 
Total horizontal moment = 433*75 

Vertical position of CE above CLR = *^"?^ = 9 35 ft. 
^ 200 

Ditt^, above bottom of keel = 10*35 ft. 

433*75 
Horizontal position of CE forward of mid-length of boat =' ^ru. =2*17 ft. 



SAILS , 



361 



Centre of Lateral Resistanee. (CLB) is the centre of gravity 
of the immersed longitudinal plane of the boat. 

Angle of Heel Produeed by Wind Pressure. — ^Referring to 
Fig. 203— 

h is the vertical height between CE and CLR. There are four 



P. 



1 



CE 



■f 



f/ 




P5 
Fio. 203. 

forces in operation and exerting an influence on the boat, viz. : 

Pi =1 The horizontal pressure of wind on sails. 

P2 =» The „ „ water on the hull. 

P3 =1 The vertical downward force of gravitation. 

P4 = The vertical upward force of buoyancy. 

Pi and P2 tend to upset the boat, acting at a leverage A. 

P3 and P4 tend to right her, and 6Z is the righting lever. 

When the vessel is at a steady angle of heel 0, we have — 

WxGZ=.PiXA 

W = the weight of the boat in lbs. 

A wind of about 14 knots (fresh breeze) is taken as giving a 
pressure of 1 lb. per sq. ft. 

For small angles of inclination — 

GZ = GM sin 

Pj =/A, where /= lbs. pressure per sq. ft., and A = area of 
sails in square feet. 

Then W X GM sin 0=/A X h 

' n /A X A 
sin =3 - - _ 

WxGM 



362 SfflPS' BOATS 

If the wind pressure is 1 lb. per sq. ft., then the formula is 

Ml 



sin 6 = 



WxGM 
WxGM 



If we invert the quantity to we arrive at the value 

of the " jpoiDer to carry saiV 

Take the example previously worked out for the position of the 
centre of effort. 

A (area of sails) = 200 sq. ft. 
h (distance between CE and CLR) == 935 ft. 

Total weight of loaded boat = 12992 lbs. (5?8 tons) 

Assume 6M = 1-5 ft. 

. . 200 X 9-35 
Then sm fl = j2992^^r5 = ° ^^ 
Angle of heel = 5 J degrees. 

If we are provided with the stability curve of a boat, area of 
sails, wind pressure, and height between centres of effort and 
lateral resistance, we can readily obtain the angle of heel, because 

WxGZ = PiXA 
and GZ = -^if 

w 

P h 
Take the value of ^ , and set this off from the base line 

of the stability curve and through it draw a parallel line cutting 
the curve at a point, which will quickly give us the angle of steady 
heel. 

Dynamical Stability expresses the amount of work done when 
incUning a boat from the upright to a given angle. It is the sum 
of the products of the force multipUed by the distance moved 
through, at every an<^'le of inchnation from the upright to the 
resulting angle of heel. 

The area of the curve of statical stabiUty up to any angle, 
measures the dynamical stability at that angle. The ordinates 
of the curve must represent the actual righting moments, i.e. the 
righting levers at any angle are multiphed by the weight of the 
boat or measure of displacement. 

In this connection we see that the greater the area enclosed by 
the curve of statical stabihty, the greater will be the amount of 
work that is necessary to be done to incline the boat to that angle 
which brings the gunwale to the surface of the water, which 



SAILS 



363 



angle, for a lifeboat, will in reality be the vanishing au|;le of 
stability. 

Relation between Stability and Wind Pressure Curves. — The 
efiective are^ of a sail becomes less as the angle of inclination 
Lucreaaes. The moment of preJ^sure is j^re-ateat when the vessel is 
upright, and is zero when the sails are horizontal or parallel to the 
water-line. 

Fig. 204 shows the statical stability curve of a ship's boat, and 
indicated thereon is also a ciirve of momenta of wind pressure 
at each angle of heel. 

If P=ithe wind preaaiire in lbs. per sq. ft., moving in 
a horizontal direction upon the Jull sail area, when the vessel 
inclines to an angle 6, correctly speaking the pressure on the 
sails => P X A X cos 6, and the effective arm = h cos $. {See 
Fig. 205.) The moments of wind pressure are set up at the 
various degrees of heel and we obtain a curve tibf (aea Fig. 204). 
The " work done " by the upsetting force of the wind up to an 
angle, say 5J°, is the area dabe, and the opposing forces to in- 
clination represented by the rigliting moments, up to the same 
angle of heel, is the area dlx: The boat will be heeled over to 
the angle at which the energy given it by the excessive wind 
pressure on the sails, is overcome by its reserve stability, i.e. to 
an inclination 1 1 V. where the shaded area bef equals dab (see 
Fig. 204). From the figure it will be seen that a sudden squall 
will probably heel the boat to twice the inclination that woidd 
be caused by a steady wind. . 

When a boat is rolling with sails set and on a leeward heel, 
i.e. inclined against the wuid pleasure, and she is suddenly 
struck by a squall, a much greater angle of inclination will be 
reached than the one previously referred to when the boat was 
struck by a squall in the upright position. 

Referring to Fig. 206. The same force of wind is blowing 

which is eslimated to incline the vessel to an angle of 5i° steady 

heel. Assuming the boat to be at a leeward roll of 11 J", and 

suddenly struck by a squall, we find under this condition 

that the righting moment and the wind pressure are acting 

together in the same direction. The boat, after reaching the 

upright condition, will continue to heel until the shaded areas 

^L (a.s previously explained) are equal. After reaching the 

^H maximum angle of inclination at 17° she will gradually return 

^H to the steady angle of heel. viz. 5p. 

^1 The theoretical consideiation, connected with the question of 

^1 sails has been reduced to a minimum, but sufficient has been 



i 



364 



SHIPS' BOATS 



stated to impress upon the reader the necessity for taking into 




W^ 7s* itcf 

- ANGLES O FH££L - 
Fio. 204. 



wr.£" 



erre^crtvc sa/l 
AR£A mA.CosB 




it. ANGLE OF 
67eAOYH££L S>C 



CI.R, 



Fro. 205. 




fo- 15* I 20* 

- ANCLCS OFHECL — 

Fia. 206. 



consideration the far-reaching effects of wind pressure on sail 
area, and their relation to the question of suitabiUty of form, to 



SAILS 



365 



provide the best qualities for enabling a boat to remain stable 
under the various conditions she may meet. 

Suitable Areas for Sails. — Table XXIV. gives in detail the 
areas in square feet for the various sails which are considered 
suitable for the particular size of boat. Figs. 207-214 illustrate 
each individual sail plan with figured dimensions. 

TABLE XXIV. 
Sail Areas fob Open Boats op Classes I. and III. 



Figure. 


Tiongth of boat 
in feet 


Type of sail. 


Area in sq. ft. 


207 


15 & 16 


Dipping lug 


79 


207a 


15 & 16 


Standing lug 


68* 


208 


17 & 18 


Dipping lug 


93 


208a 


17 & 18 


Standing lug 


72* 


209 


19&20 


Dipping lug 


120 


209a 


19 & 20 


Standing lug 


91* 


210 


21 &22 


Dipping lug 


138 


210a 


21 &22 


Standing lug 


112* 


211 


23&24 


( Standing lug 
\Jib 


124 

28 


211a 


23&24 


Standing lug 


138* 


212 


25 & 26 


(Standing lug 
IJib 


145* 
30* 


213 


1 27 & 28 


(Standing lug 
\Jib 


165* 
34* 


214 


29 & 30 


/Standing lug 
\Jib 


198* 
38* 



* Sizes approved by the Board of Trade. 

In Figs. 207-211 there is shown in addition to the dipping 
lug-sail, a standing lug indicated in ticked lines. It has been 
advocated by many ships' officers and practical boatbuilders 
that the position of the rriast, when the boat carries a single lug, 
is at the first thwart, to enable the tack of the sail to be brought 
down to the head of the stem, and thus allow the boat to sail close 
to the wind. Recently there has been an alteration in the 
governing regulations, making it permissible to fit the mast at 
the second thwart with a standing lug sail. This recommendation 
appears to be opposed to all the rules of sailing, but the details 
are inserted for general information. 

The areas and details shown in full lines in the various plans 
referred to are suggested as the most suitable for the purpose of 
providing a rapid means of reaching safety when the conditions 
of wind and weather will allow. The areas are considered to be 



366 



SHIPS' BOATS 



sufficient for the purpose, and at the same time not too large 
to become detrimental to the boat's stability. They have been 




Fra. 207. — Sail plan for 16 and 16-ft. open boats of Glasses I. and III. 

drawn up by practical sailmakers and worked-to by a large number 
of boatbuilders during the past three years. It naturally follows 
that perniission^for fitting a standing lug at the second thwart 




Fig. 208. — Sail plan for 17 and 18-ft. oi>en boats of Classes I. and III. 

will be followed by the majority of the firms, in view of the 
reduced cost, and the enforcement of standard regulations. 



SAILS 



367 



There is quite a divided opinion as to whether it is essential 
or advisable to fit all the lifeboats of a foreign-going passenger 



A 



/ 



4 



1r. 



^i. 




Fio. 209. — Sail plan for 19 and 20-ft. open boats of Classes I. and Til. 

steamer, employed in the North Atlantic trade, with masts and 
sails. Provided the vessels are fitted with wireless telegraphy 




y. jo^o — 



F[0. 210.--Sail plan for 21 and 22ft. open boats of Classes T. and III. 



apparatus, the Life-saving AppUances Rules make provision that 
only four of the lifeboats need be equipped with masts and sails. 



368 



SHIPS' BOATS 



One of the reasons for the inclusion of this clause is that when 




Fio.| 211.— Sail plan for 23rand^24-ft.'open boate of Class I. 




Fio. 212.— Sail plan for 25 and 2(>-ft. oik-u boata of Class I. 

disaster overtakes a vessel, it is naturally assumed that wireless 
messages have been despatched, giving the exact position, 



SAILS 



369 




Fio. 213. — Sail plan for 27 and 28-ft. open boats of Class I. 




Fio. 214.— Sail plan for 29 and 30-ft. open boats o| Class I. 

and it is therefore to the advantage of the occupants to stay 
within the immediate neighbourhood of the disaster until the 

2 B 



370 SHIPS' BOATS 

arrival of help. The boats should keep within reasonable distance 
of each other, and ride with the aid of the sea anchor. If all the 
boats are equipped with sails, and efforts were mcMie to set sail 
in favourable weather, they might get widely separated, and the 
operation of rescue would become increasingly difficult. It 
largely depends on circumstances, and the position or area in 
which the disaster occurs. It usually happens that the pre- 
vailing conditions, when serious difficulty overtakes a vessel, 
are quite the opposite to what were anticipated ; however, if the 
occupants of a lifeboat are within reasonable distance of land, a 
spread of sail is considered an advantage to enable them to arrive 
at a port as quickly as possible, particularly when there are 
wounded persons on board. 

The boats for Home Trade vessels need not be Supplied with 
masts and sails, as the distance separating the port of departure 
and arrival is not considered sufficient to demand their inclusion 
in the equipment. In isolated cases they have been provided 
at the direct wish of the shipowner. The seamen of vessels 
thus equipped, during the submarine menace around the coasts 
of Great Britain, derived a great advantage from the inclusion 
of some means of propulsion beyond the use of oars, which 
lessened their sufferings when it became necessary to abandon 
the ship. 

There is one point to which attention is particularly drawn. 
In the case of certain foreign-going cargo vessels, boats of Class III. 
are included in the statutory equipment. They must, therefore, 
be fitted with masts and sails, and equipped in every particular 
like the remaining lifeboats, except that buoyancy-tanks are not 
required to be fitted. 

Details of Sails. — The various parts of a sail are illustrated 
in Fig. 215. 

Tlie material of all t>ails should be made from good quaUty 
linen duck or an approved canvas. 

The threads of the sail cloth worked across are called the 
'* ivvjtr and those which run in the opposite direction over and 
under the weft are calleil the *' icarp.^' The " selvage " is the 
edge of the doth. 

The cloth is cut in relation to the run of the " weft " and 
" war}),'' taking into account the amount of stretching which 
takes place, so as to give the best results for a good setting sail. 

It is iionerallv considered that a ''flat " sail is the best form of 
sail to enable a boat to sail close to the wind. A bagg}' sail tends 
to burv the bow of a boat and hold her back. A flat sail has more 



SAILS 



371 



lifting power, and while securing the maximum amount of wind 
pressure, allows the air easier freedom for exit from the after 
leach. 

A well-made sail can be spoiled by the operation of bending. 
A lug-sail must be fairly slack when first bent on the yard. The 
peak and throat are secured to the yard by seizing, and the lacing 
should be commenced from the centre of the yard, working 
towards the peak and throat. The usual practice is to reeve 
the lacing through the eyelet-hole in the sail, over the yard, and 
bring it back through the same eyelet-hole, make a half-hitch, 



SMfKMO 
HOOP 



MEAD 




SO/r 



Fig. 216. — ^Details of sails. 



and work the lacing along the head of the sail to the next eyelet- 
hole, until the operation is completed at the peak and throat by 
securing the lacing by two half-hitches. 

The sails should be used once or twice to provide for stretching, 
and then rebent on the yards. 

The holes in the yards which take the seizings for peak and 
throat, are usually kept about 6 in. beyond the length of the head 
of sail, to allow for stretching. 

The position of the strop on the yard, which is attached to the 
halyards, is of some importance, to enable the sail to set properly. 
The position for a lug-sail can be found by actual trial when first 



372 



SHIPS' BOATS 



spreading the sails, but roughly indicated, the position for a 
dipping lug is at about one-third the length of the yard from its 
fore end, and a quarter the length for a standing lug. 

The bolt rope should be of substantial dimensions and quality 
and worked the full length of the lu£E and head of sail, also at the 
edges of the clew and peak. 

Each sail must be fitted with reef points, and a substanticJ 
thimble and cringle secured at the clew and tack. 

The usual practice has been to fit a standing lug and a jib for 
boats down to and including 24 ft. in length, the mast being 
stepped at the second thwart. 

In boats of 23 ft. in length and under, a dipping lug only is 





ELEVATION SECTION 

Fig. 216. — Method of fitting tack hooks. 



fitted, with the mast stepped at the first thwart, so as to aUow 
the tack of the sail being brought down to the head of the stem. 

To facilitate the operation of dipping the sail, a " tack hook " 
is fitted on the stem or apron head, usually behind the breasthook, 
as shown in Fig. 216. The sail is not lowered when dipping, but 
the halyards are slackened sufficiently to allow the tack to be un- 
hooked at the stem. The fore yardarm is then dipped from one 
side of the mast to the other, the tack being re-hooked at its 
original position. 

It used to be quite a common practice to fit the mast at the 
second thwart, with only a standing lug-sail ; this is a practice 
which should be condemned. 

]A boat fitted with a dipping lug having the tack brought 
down to the stem or with a standing lug and a jib, is able to sail 
closer to the wind with less drift to leeward, and possesses greater 



W lug gtt* 



SAILS 



373 



liiting power than a boat which ia only supplied with a standing 
lug fitted at the second thwart. The first method also helps 
to keep the boat from pitching in a head sea. 

Sail Bag. — A painted canvas sail bag is not a requirement 
of the L.S.A. Rules, but it is a very necessary inclusion in the 
equipment of a boat, The writer has repeatedly seen aaila made 
useless by the action of the weather, a difficulty which can easily 
be remedied by the provision of a suitable cover. 

Shrouds. — Every boat supphed with masta or sails should be 
fitted with wire or suitable hemp shrouds on each side of the 
mast, set up to proper shrciud plat*a of good quality and secured 
with through clenched fastenings. Fig. 197 b shows the usual 
shape of plate supplied for the purpose. 

A common practice is simply to fit a plate of sufficient depth 
to suit the gunwale, and secured to the latter by a couple of 
screws. The most satisfactory type of fitting is a substantial 
plate secured on the outside of the sheer atrake, joggled over 
the rubber and fastened by through clenched fastenings at the 
gunwale and rubber. 

It is considered shoddy work to simply splice the shrouds over 
the peak of the mast; proper iron hoops should be fitted as shown 
in Fig. 219. 

Mast Hasp,— This should he of substantial scantling and so 
arranged that the securing pin is easily inserted and withdrawn, 
The necessity for driviug tlie securing pin must be avoided for 
obvious reasons. The arms of the hasp are secured to the thwarts 
by through copper rivets well clenchwi, as indicated in Fig. 217, 
or by ordinary nut and screw bolts, the nuts being hove up on 
the arm under the thwart. Securing the arms by ordinary screws 
is a useless and dancerous practice. 

Two niethorls of forming the mast hasp are shown in Figs. 217 
and 318. The latter is considered the better job of the two. 
More time is necessarily taken in fitting the mast, conse- 
quently, greater expense is incurred, but the additional outlay ia 
more than compensated by the provision of a better security at 
the thwart, which relieves the stress on the mast step. 

Details of mast steps are dealt with in Section A of Part IV. 

Halyard Sheaves.— Care must of necessity be taken in fitting 
the mast sheaves to take the jib and lug-sail halyards. The jib 
is fitted above the lug sheave, and both look in a fore-and-aft 
direction. 

The sheaves are securely attached to the mast with a clenched 
bolt or pin, and not simply driven in from one side only, to avoid 



374 



SfflPS' BOATS 



clenching. It is these small detail fittings, slovenly attached to 
the mast, and considered of little importance, which are responsible 
for many difficulties. 

To prevent the mast swelling through the action of the weather 
and jamming the sheave, sheet copper should be neatly tacked 
in and around the slot in the mast as shown in Fig. 220. 

Mast Traveller. — A convenient form of mast traveller is 
shown in Fig. 221 ; the fitting should be of substantial section 
and of such a pattern that when hoisted by the halyards it does 




u 



/4 



3 — ^ 



V 4' \! ^ 






- eL£V AT/ON 







;4 CoppcR 




- PlAN- 



^\ © Q Q^ 




Fig. 217. Fio. 218. 

Details of mast clam^is and hasps. 

not jam with the mast. The experience of the writer may have 
been an unfortunate one in this respect, but it is safe to say that a 
large number of these detailed, but nevertheless important, 
fittin<^^s, connected with the rigging of ships* boats, now placed 
on the market, are considered very poor and unsuitable for the 
purpose required. 

it will be noticed that the type of traveller shown in Fig. 221, 
has the (ye of the hook attached to the halyards, and so shaped 
as to allow the traveller to slip up the mast easily, and without 
a.ssi.stance by any other means than the halyards. 



SAILS - 375 

Sheet Cleats.— The sheets atfiiched to the clew of the jib 




AthwarWhip view. Fore-and-aft viow. 

Fia 221. — DcUils of most trsTollcr. 

should l>n dimble, and led through eye-plat«B out of the way of 
tlie passenj;er3, to strong cleats attached to the gunwale in the 



376 



SHIPS' BOATS 



stem-sheets. The cleats for securing the sheet attached to the 
clew of the lug-sail, are usually fitted just abaft the knee on the 
aftermost thwart, so that all the sheet ropes are under the 
control of the officer in the stem-sheets. 

A typical sheet cleat is shown in Fig. 197 a. It is the usual 
type, but it should be well secured to the gunwale and large 
enough for the purpose for which it is intended. 

Length of Masts. — The length of masts must not exceed 
two-thirds the length of the boat. Table XXV. gives the lengths 
for the various open boats of Classes I. and 'III. The length is 
taken from the heel of the mast to the centre of the upper halyard 
sheave, so that when the normal peak is given to the lug-sail the 
steersman will have no difficulty in possessing a full unobstructed 
view under the foot of the sail. 



TABLE XXV. 
Length and Sizes of Masts for Open Boats of Classes I. and III. 



LengU) of Boat iu feet. 


Length of Mugt 
from heel to centre of 
upper halyard sheave. 

10' 0" 


Diameter of Mast 
at thwart 
in inches. 


15 & 16 


2j" 
3^' 


17 & 18 


iro" 


19 &20 


12' 6" 


.Si" 


21 &22 


14' 0" 


3i" 


23 & 24 


15' 0" 


3}" 


25 & 2H 


hV 0" 


4" 


27 &28 


18' 0" 


4J" 


29 & 30 


19' 0" 


4i" 



Note. — Tlic above lengths of masts are in accordance with the Board of 
Trade standard sail areas. If dipping lug-sails aie fitted, the full length of 
mast is required, equal to two-thirds the length of the boat; e.g. a 16-ft. dinghy 
requires a mast 10' 8" in length. 

The diameter of yards to be from 2"-2J" for a left, boat to 2J"-3J" for 
a 30-ft. boat, which is governed by the length of head. 

The masts are usually made from well-seasoned Norway 
spruce. They should be coated wath varnish, or white-lead paint, 
as a protection against the weather. Ordinary white pine is of 
little value, as it quickly spht^, and is unsuitable for spars. 

An old nile for obtaining the diameter of ships' masts was 
1 in., and for cutters £ in. for every 3 ft. of length. This is 
hardly apphcable for masts of ships* boats, as it would make them 
too heavy for the operation of stepping, which might probably 
have to be done when the boat is full of persons. Nevertheless, 
the mast must be strong enough to carry the approved area of sail. 



METHODS OF GALVANISING 



37T 



I 



The practice of fitting a standard aize of mast hasp for all 
sizes of boate should be condemned. It stands to reason that 
the smaller boat^ are overweighted with so lieavy a mast, while 
the larger ones are supplied with masts insufficient in strength. 
The reference may appeal to some builders who limit their stock 
of fittinf;s to small proportions. 

General Remarks.—Carelesaneas and insufficient attention 
to small details often spoil the good work put into the actual 
construction of the boat. It is the extra ten minutes spent on 
the " finishing off," althougli not materially affecting the boat as 
a hfe-saving appliance, that undoubt«dly adds to the appearance 
and increases her lasting qualities. 

If a mechanic is given good material to work with he will 
naturally take a more personal interest in the construction, and 
endeavour to produce a boat that will be consistent with the 
quality of the material. In a similar way, if boats of l^e 
highest class are placed on board passenger and cargo veesek, 
having a good finished appearance, the ship's officer responsible 
for the upkeep of the lifeboats will take a keener interest in his 
work than if the boats are poorly constructed and lack a finished 
appearance. Ships' officers do not profess to be boatbuilders, 
but experience has taught them what equijmient is necessary, 
and the quafity of details which should be provided in order 
that they may be effective for the purpose they have to serve. 

There is no doubt, for many years, that insufficient attention 
has been paid by shipbuilders and boatbuilders to the question 
of providing suitable sails and their component details. In 
fairness to the builders, it should be stated that the ruies and 
regulations were not clear on the -subject. However, the reference 
to the importance of these matters is not considered out of place. 



SECTION C— METHODS OF GALVANISING 

It is very essential in the construction of all metallic bnata and 
fife-rafts, that the steel or iron should be carefully and efficiently 
galvanised. One of the difficulties which meets the builder is 
that of securing a satisfactorj- system of galvanising in way of 
those portions of the hull which have been welded together. 

The standard practice in the boat-yards of Great Britain is 
to galvanise the steel plating of metallic boats inside and outside, 
with the addition of a coating of bitumastic enamel on the inaide, 
if desired. 

The United States Steamboat Inspection Service requires all 



378 SHIPS' BOATS 

the shell plates, air-tanks, nails, gunwale braces, rudder braces, 
and fastenings of metallic boats to be galvanised. 

The riveting must, therefore, be performed in such a manner 
as to prevent the galvanised surface of the plates from becoming 
injured, and exposed to the corrosive effect of sea air, and water. 

Corrosion is the deadly enemy of the metaUic boat. It 
therefore becomes necessary to frequently inspect the interior to 
ascertain the actual condition of the hull^ 

An internal coating of some protective composition goes a 
long way towards the prevention of the difficulty, as frequent 
observation during the survey of boats has often proved. 

All iron or steel work used in the construction of wooden life- 
boats must be heavily galvanised. The omission of the hooks from 
this requirement depends largely on the process by which the iron 
is treated. If the material is galvanised by the hot dipping system, 
the structure of the metal is exposed to imeven stresses by being 
suddenly plunged into a very high temperature without the 
opportunity to gradually cool. Consequently, the material has 
a tendency to become brittle. A system known as that of 
sherardising is well adapted to the requirements of the boat- 
builder in this respect, and no weakening effect takes place in the 
material during the process of galvanising. 

Whenever iron or steel lifting hooks have been galvanised 
by the hot dipping process, they should be tested after galvanising, 
and not before. 

Of two evils choose the less. The general practice has been 
to galvanise the keel plates, and thickly coat the Ufting hooks 
with a protective paint. Taking into consideration the dele- 
terious efTect of the action of water, etc., on the heel otthe shank 
of the lifting hook, which is usually hidden from sight, it is 
advisable to galvanise the whole of the iron or steel work. 

Hot Dipping Process. — The iron is first placed in a vat of 
dilute acid, to remove all rust and clean the surface for the proper 
adhesion of the zinc. It is then heated and inserted in molten 
zinc, which is covered with a layer of sal-ammoniac to prevent 
evaporation. 

The iron thus becomes coated with a thin covering of zinc, 
which will stand many years if exposed to ordinary wear, but 
the action of sea air has a penetrating effect upon the zinc, and 
it becomes essential to watch for any signs of con'osion, particu- 
larly in way of the liftin^^-hook keel plates. 

It is not the actual coating of the material with the zinc 
dej)()sit which makes the iron brittle, but the influence of the 



METHODS OF GALVANISING 379 

previous operation of immersing the iron in the vitriol bath. The 
latter may be too heavily charged with acid in order to quickly 
clean the material, and the combined action of the acid and the 
hot zinc gives an appearance to the iron as if the grain had opened 
out into long fissures, making the material useless for the purpose 
required. 

Another drawback to this process is, when bolts are served to 
the boatbuilder in their black condition, it becomes necessary 
after they are galvanised to run down the threads, consequently 
the builder takes the line of least resistance, and coats them with 
galvanising paint, which is of little value. All securing bolts 
should, therefore, be galvanised at the maker's works before 
delivery. 

Sherardising. — This process differs from the electric and hot 
dipping systems of galvanising, and has often been referred to as 
a process of dry galvanising ; but it practically fulfils the same 
object of covering iron or steel with a coating of zinc in order to 
render them rustproof. 

Briefly explained, the process consists of placing the articles 
in closed drums or other suitable receptacles, in contact with the 
ordinary zinc dust of commerce. The drum is then placed in an 
oven and gradually heated to the required temperature, and 
allowed to remain for a given period. It is then permitted to 
cool down very gradually, and the articles when taken out of 
the drum are found to be evenly coated with pure zinc. 

The articles are passed through an acid bath before being 
placed in the galvanising drums, to clean the surface for the 
proper adhesion of the zinc. Care has to be exercised in 
diluting this pickUng bath, to avoid the difficulties previously 
referred to. 

The temperature used when coating the article with zinc 
ranges from 400° to 600° Fahr., but in no case does it reach the 
melting point of zinc, viz. 788° Fahr. The action of the zinc is 
to root itself into the material, forming a surface alloy ; 
when a thick coating has been deposited, the top portion may be 
brittle, and although it may scale or crack off, it leaves under- 
neath a malleable metallic coating, and below that again the 
surface allov. 

The coating is of a very smooth nature, and does not fill up 
any interstices or leave an uneven surface, and thus the shape 
of the article is preserved. Consequently, bolts and screws 
which have been threaded can be galvanised without the necessity 
of re-cutting the threads. 



380 SfflPS' BOATS 

Another advantage is, that it covers every portion of the article 
and penetrates the smallest holes, and sherardises them without 
clogging up. The surface can be readily polished without the 
zinc being rubbed off. 

In the ordinary hot dipping process, the iron receives a thin 
coating of zinc, which, owing to its brittle nature, may crack, 
and the influence of the damp sea air will thus get behind the 
zinc and the metal, and rusting action is set up. The sherardising 
process largely obviates this trouble. 

No sudden high temperature is brought on the material, and 
the gradual cooling down subjects the iron to a process of 
annealing. 

The whole system lends itself to the best results for galvanising 
lifting hooks, screw bolts, nuts, breasthooks, thwart knees, angle 
lugs, etc., used in the construction of ships' boats, giving a highly 
finished appearance and providing a permanent and satisfactory 
coating for the prevention of corrosion. 

Electro-Galvanising. — The process of electro-galvanising is 
very simple and effective, provided in the first place the plant 
has been well designed and constructed by engineers of experience, 
who also possess both a practical and theoretical knowledge of 
the subject. 

A great amount of power and labour is sometimes lost 
through the installation of unsuitable types of generators and 
badly constructed tanks. 

There are several advantages associated with the electro- 
proce.ss wliich account for its extensive use in the United States 
of America and Great Britain, one of the most important of 
which is that throuf^hout the operation, the articles to be galvanised 
are not subjected to f^aeat heat, and the physical properties of 
the material are, therefore, not interfered with. This is a 
very important feature in connection with the strength of lifting 
hooks, davit blocks, and other gear associated with life-saving 
appliances, wliich cannot be overlooked. Another advantage 
is that, during the whole process of galvanising, gases are not 
liberated, but this lart^'ely depends upon the quality of the 
solution used in the electrolyte. The surface of the zinc deposit 
is very smooth, evenly distributed, and can be poUshed if con- 
sidered nocessary for a particular purpose. 

Tlie wochis o})erandi for <ralvanising such articles as are used 
in the construction of shi})s' boats and davit gear, is briefly 
describiHl as follows : — 

Th(^ surface of the article is first of all cleaned with gasoline 



r 
I 



METHODS OF GALVANISING 



381 



L 



to remove all traces of greaae. It is tlien placed in a potash or 
acid bath to eliminate any oil that may be left ou the article, 
an<J afterwards thoroughly washed in water. It may be further 
subjected to a cleaning process from a sand blast, which removes 
all appearances of rust. 

The procedure of cleaning may vary in different eatablish- 
mente, but the main object is to absolutely clean the surface of 
the article of all chemicals to ensure that the zinc will adhere. 
The article is then placed In a pickling bath containing a mixture 
of hydrochloric acid and water, afterwards thoroughly washed, 
and taken to the tank or electrolyte charged with the zinc 
solution for plating. 

The supply of current to the electrolyte ia received from 
generators of low voltage, which enables the articles to be handled 
by the operators with freedom and safety. 

Zinc plates or anodes are suBpende4 to the anode bai-s, which 
are connected to the positive pole of the current and are situated 
at the side of the tardc. 

The articles to be galvanised arc totally immersed in the 
solution, but suspended from tlie cathode bar running over the 
centre and top of the tank, and connected to the negative pole 
of the current. 

The standard solution supphed by the Galvanising Corporation 
of America, Brooklyn, N.Y., with which the writer has had some 
experience, is self-sustaining, and does not require any additions 
beyond a little water when the density is increased. This high 
standard of efficiency for any solution can only be maintained 
if the plant is kept free from leakage, etc. 

The amount of zinc deposited on the article depends on the 
form of surface to be coated. An irregular surface means an 
uneven distribution, e.g. an article which has been screw-threaded, 
requires to be left in the plating tank a longer time than if it 
were a plane surface ; or the voltage of the current increased, in 
order that the zinc deposit may reach the recesses of the screw 
threads. The amount of zinc deposited, therefore, depends on 
the number of ampere-hours of current used. 

The action of the electric current is to decompose the solution, 
and the zinc is deposited on the surface of the article. The 
solution for the moment has, therefore, lost some of the zinc which 
it originally contained, and it immediately reacts on the zdnc 
anodes attached to the positive pole of the electric current 
received from the generators, so that the solution is constantly 
and automatically kept up to full strength. 



382 SHIPS' BOATS 

The usual thickness of the galvanised coating is about half 
an ounce for every square foot of surface. 

The efficiency of the operation depends largely on the quality 
of the solution, maintaining pure zinc in the electrolyte without 
mixing with gases of a detrimental nature, and depositing the same 
in this condition on the surface of the article. It is also essential 
for the solution to have a high power of conductivity in order to 
" throw in '' the zinc to the innermost recesses in ihe article to 
be galvanised, so that the surface may remain smooth, uniform, 
and not become porous or spongy. 

After the articles have been suspended in the solution for the 
required time, they are taken out of the plating tank, placed in 
the hot water bath, and then stacked for drying. 

SECTION D.— PAINTING 

Keference has already been made in Section A of Part IV. to 
the importance of coating the faying surfaces of all material with 
paint of good quality, as progress is made on the construction of 
wooden boats. 

Some shipowners demand that the boat must be covered with 
two good soaking coats of boiled linseed oil, and allowed to dry 
before the usual number of coats of paint are applied. The 
inclusion of such a clause in a specification can be well recom- 
mended, as it extends the life of a boat and increases the resisting 
quabties of the planking to the effects of the weather and the 
changes of atmosphere. 

As each particular detail of the combination in the frame is 
worked, the faying surfaces should be thickly covered with good 
white-lead paint, particularly in way of the hog piece, keel, 
deadwoods, apron, and stem or stempost. The landing edges 
of the planks, when the clinker method is being used, and the 
various details of the box gunwale and capping piece, should also 
be painted before they are secured in position. 

The most important protective covering the boat receives 
is that which is appUed to the inside of the planking before the 
timbers are worked. This should be undertaken so that the 
paint has an opportunity to dry over the week-end. There is a 
tendency with many of the boatbuilders to mix too large a pro- 
portion of dryers with the paint in order to allow the work of 
timberinii; to proceed with rapidity, and in so doing the object 
in applying this first coat is defeated. 

The instructions issued by the Board of Trade demand three 



^H coats of 
^P twocoal4 



PAINTING 



383 



I 



coals of the best white-lead paint to be applied on the outside and 
ttvo coai^ on the inside. Care should be taken to let each individual 
coat dry before the second or third coat is applied. Attention 
should be paid by the inspector to see that the second coat of 
paint is applied to the planking and timbers before the buoyancy 
air-cases are inserted, and the tank cleadinj; secured ui position. 

Where lifeboats have been constructed of material unsuitable 
for the trade in which the vessel is engaged, and where the heat of 
the tropics has a detrimental effect on the planking, it has some- 
tiniBH become necessary to thickly coat the inside of the plank- 
ing with a bitumastic enamel, as the plastic nature of this 
composition enables the seams to preserve a watertight joint. 

I'he necessity for resorting Ut this method should never arise 
if vessels engaged in tropical waters have their boats constructed 
of teak, mahogany, or steel, and the material is well seasoned. 

Where boats are subjected to great beat, or altematii^ con- 
ditions of heat and cold, it is absolutely necessary for the material 
to be thoroughly seasoned, and it cannot be expected that the paint 
will cover up a "multitude of sins." The necessity for the 
application of bitumastic enamel on wooden boats should never 
arise if ordinary precautions are taken, and the authorities demand 
the most suitable woods to be used in the construction of boats, 
having in view the particular service in which they will be 
engaged. The responsibihty of the shipowner should not be 
limited in this respect. 

Paint is made up from five constituents, viz., a base, vehicle, 
drier, solvent, and a colouring pigment. 

The base is the main substance which gives the necessary 
body and covering power. 

The vehicle is a semi-liquid which when combined with the 
base allows it to be spread on the surface of the material with a 
brush, in a thin and sufficient quantity. 

The base and the vehicle are the two important essentials. 

In order to permit the base to dry with reasonable rapidity 
and maintain the proper degree of hardness, driers are added to 
the mixture. 

To give the required thinning power and freeness to flow, a 
solvent must also be included. 

The 'pigment is simply added to give the necessary colour for 
decorative purposes. 

It is necessary to understand the nature of these constituents 
when mixing up the paint for the purpose required, so as to obtain 
the beat results. 



384 SHIPS' BOATS 

The presence of resin causes paint to crack after a time of 
exposure, while that of driers also produces the same effect. 

Turps oxidises on exposure to air, becomes converted into a 
resinous substance, and has little of the weather-resisting pro- 
perties of oil. It should therefore be used on external work only 
in sufficient quantity to make the paint flow readily from the 
brush. 

The use of naphtha should be strongly condenmed, and every 
care must be taken to prevent the excessive application of large 
quantities of driers. 

White-lead is the most common base that is used for paint 
in boatbuilding. It is usually prepared in the form of powder 
and combined with refined linseed oil. It tends to become 
darker when exposed to the sea air and changes in composition. 
It has the disadvantage of possessing poisonous qualities. 

Zinc white, or oxide of zinc, is pure white in colour, possesses 
greater covering power than white-lead, does not affect the linseed 
oil in the same way as the latter ; is non-poisonous, and is not 
affected by the sea air. 

Linseed oil is produced from the ripe flax seed by compression. 
It is pale in colour, and best used in association with a base for 
internal work. 

In its raw state it becomes oxidised when exposed to the 
weather and dries very slowly. Boiled linseed oil dries much 
quicker than tlie raw material, and its weather-resisting qualities 
are greatly increased by the boiling process. 

Spiritii of turpentine is the only solvent that is used with paint 
when mixed with oil, and then only to a Umited degree, and in 
sufficient quantity to allow tlie paint to be easily worked with a 
brush. There is very little power in the turpentine to resist the 
effect of the weather when exposed to the sea air, as it oxidises 
and eventually perishes. It is obtained as a result of distilling 
the crude turpentine secured from the pine and larch trees, the 
residuum beini; resin. 

The followini^ compositions are freely used, and can be. recom- 
mended for all work in connection with the construction of 
ships' boats : — 

TJie Mercantile Marine Sermce. 

Best white-lead . , 1 cwt. 

Patent driers 14 lbs. 

Raw linseed oil 3J galls. 

Spirits of turpentine 1 quart. 



PAINTING 385 

The British AdmiraUy. 
Great Paint — 

Genuine white-lead 73 lbs. 

Ordinary black 8f^ lbs. 

Turpentine substitute 6 pints. 

Raw linseed oil 16 pints. 

Marine driers 7 lbs. 

White Paint— 

Genuine white- lead ....... 84 lbs. 

Marine driers 7 lbs. 

Raw linseed oil 13 pints. 

Turpentine substitute 6J pints. 

Varnishes are divided into two classes, oil and spirit. The 
former is used for outdoor work, where the material is exposed 
to the effect of the weather, and the latter should only be 
used for interiors. 

The gums, which are obtained by the process of tapping certain 
trees, mostly pines, contain two substances, an oil, which after 
treatment by evaporation leaves a residuum, called resin. The 
resisting property is the resin itself ; hard resin is bright, but 
brittle, while the soft resin is more elastic, due to the proportion 
of oil it contains. 

Amber and copal are two good oil varnishes ; the former is 
foimd around the Baltic, and the latter obtained from the East 
and West Indies. 

Lac varnish is a spirit varnish and cannot withstand the effect 
of rain or the action of the sun. Resin varnish must be 
avoided altogether, being a production from turpentine, which 
quickly[|cracks and peels off when exposed to the weather. 

Oil varnishes are usually made from a particular resin, 
associated with linseed oil and thinned with turpentine. Spirit 
varnish is composed of another quality of resin which is dissolved 
in methylated spirits. 

Immediately the stem and stempost are erected, it is a great 
advantage to coat them with an oil varnish as a protection from 
the weather, and to prevent the oak from opening out during 
the period of construction. 

It is usual to varnish the outside of the upper strakes, the 
rubbers, and the gunwales, with two coats of good oil varnish. 

Every portion of the boat should be painted, particularly 
those portions which are not exposed to view, e.g. the underside 

2 c 



386 SHIPS' BOATS 

of all thwarts and side benches. The extra ten minutes spent 
on the operation of painting makes all the difference to the 
appearance of a boat. 

Putty should be very sparingly used, and its application 
practically confined to the keel seam and hoodedends of planks. 
An inferior quahty of putty is made from whiting and oil, which 
very quickly deteriorates when exposed to the weather. It 
should, therefore, be composed of the best white-lead with boiled 
Unseed oil, and worked into the seams with a wooden tool shaped 
like a pencil. 

SECTION E.— REPAIRS AND MAINTENANCE 

OF BOATS 

When lifeboats have been constructed in accordance with a good 
specification, and the workmanship, together with the material, 
are of a high standard, the necessity for repairs will be practically 
confined to cases of actual damage, instead of the constant process 
of patching up, which is bound to occur when boats are con- 
structed to the ideas of persons who are not controlled by standard 
and detailed regulations. 

The action of the British Board of Trade acting in co-operation 
with the boatbuilders throughout the United Kingdom, including 
the Boat, Yacht, and AUied Trades Association, in maintaining a 
standard specification with full details of scantlings, etc., is 
greatly to be commended, and will obviate the necessity of boats 
coming into the hands of the repairers with the frequency which 
has hitherto been associated with boatbuilding. 

The responsibility for upkeep will now rest almost entirely 
with the ship's officers, and if a little attention and oversight 
are paid to the boats when in regular service on a vessel, the 
result will be a considerable saving to the shipowner. 

The initial trouble which has boon responsible for many leaky 
boats, was originally caused through the use of unseasoned 
material and defective plank seams. 

The practice of caulking a thread of cotton into all the plank 
seams of a clinker-built boat should be discouraged. It naturally 
follows that le.ss care will be exercised by the workman during 
the important process of fitting the plank landings, because he 
relies on the cauUdng to make good what he has omitted during 
the progress of constniction. Even if the thread of cotton were 
inserted between the landings before t^he fastenings were hardened 
up, it would have some reason to commend itself, but it is the 



REPAIRS AND MAINTENANCE OF BOATS 387 

writer's (ipinion, that it is to the advantage of the boat if the 
,ma iire fitted close toj^etlier without the insertion of any 
parking, beyond a good thick coat of paint, or the apphcatiun 
of " blair." 

It inevitably follows, even when the seams are puttied, that 
the cotton will begin to swell after a time, and bring an uudue 
stress on the plank fastenings, with the inevitable consequence, 
sooner or later, that the planks will split along the landing. 
This trouble has been a common nccurrencp, and responsible for 
much dissatisfaction among shipowners. 

When considering the question of repairs, we should keep in 
mind the necessity t^> avoid taking out a plank except when it 
is absolutely essential. 

If the seams or landings of the planks are generally leaky, 
they should be lightly caidked, because the material will be seasoned 
after the boat has been exposed on the boat deck of a vessel. 
The plank and timber fastenings should be hardened up, and the 
seams well puttied inside and out. Instead of the light caulk, 
pouring in a ajliition of Stockholm tar, bitumastic enamel, marine 
glue, or other such elastic solution, mixed with a httle flock or 
thinly shredded oakum, between the landing edges, will overcome 
the difficulty. The drawback to the use of a bitumastic enamel 
is foimd when the heat of the sun causes the solution to run 
through the landings and discolour the paint on the outside of the 
boat. 

When a lifeboat comes in for periodical survey and overhaul, 
one naturally looks at particular portions of the structure for 
signs of trouble. The butts of the planking should be carefiUIy 
examined, particularly at the hooded ends. The keel seams, 
the planks and landings in way of the stowage chocks, the con- 
dition of the stem and stempost scarphs at the keel, the lifting 
hooks, keel plates, and deadwoods; should be carefully inspected. 
Attention should be paid to any signs of broken timbers. 

If the boat has been thickly coated with paint, this should be 
burnt oS, but in any case the paint sliould be scraped off the 
plank scarphs or butts. 

It is usually foimd necessary to strip out the cotton from the 
hooded ends of the planks, refast«n with a row of \nans screws, 
recaulk, and till the seams with putty. 
The keel seam is usually re-caulkcd. 
Broken timbers are best dealt with by fi^ 
timbers adjacent to the old ones, and in one lein^" 
piece, and running them up as high above th«^ 



388 



SHIPS' BOATS 



seats will allow, care being exercised not to split tiie plank 
landings. 

Split planks must be taken out if situated below ihe binding 
strake, but the operation should only be tuidertaken by a boat- 
builder, otherwise, inexperienced hands will do more barm than 
good to the adjacent planks. 

A temporary repair can be made by fitting a doubling on the 
inside of the plank if the damage is not extensive, or by securing 
an outside doubling as shown in Fig. 222, and well bedding the 
f a}dng surfaces with thick white-lead paint. 

Sheet lead tacked on the outside of the planking will keep the 
boat tight until proper repairs can be undertaken in port. 



m 



M 



k 









• O ' 



o : 



/?0(/s///x{P 



o : 



■ o 




. o . 



suvr/fffi 



TfMBe/f 



¥ 



V 







J>OU8l/flK 



ELEVATION 



SECTION 



Fig. 222. — Botails of doubling to a damaged plank. 



Any disturbance to the binding strake should be avoided, 
and local attention given to the damage rather than interfere 
with the strake as a whole. 

Broken gunwales of the sohd type are not infrequent, brought 
about through the lack of proper incorporation witii the timbers, 
and the lack of a good stout rope fender. To take out the full 
length of gunwale is a difficult operation, and if the damage 
is confined to one place, a compromise may be effected by 
scarphing a new piece into the main portion of the original 
gunwale. The scarph should be at least 12 in. in length, with a 
stout doubhng piece fitted under the gunwale, extending for a 
lengtli of 2 ft., and secured as illustrated in Fig. 223 a. 

The United States Steamboat Inspection Service permits new 
])oats to be constnictc^d with gunwales made in two lengt'hs. 



"REPAIKS and maintenance of boats 389 

being scarphed with a good long bevel or lip, and stiflEened on the 
underside by a piece of gunwale material at least 2 ft. in length, 
1 J in. thick, and the width of the gunwale. 

If the plank edges of a clinker-built boat are damaged in way 
of the stowing chocks, and have become worn through the con- 
tinual rubbing when settling the boat into position to fix the 
gripes, compensation can be given by fitting pad pieces from the 



UPPr^ SrRAKE 




A. -DETAIL or GUNWALE SCARPH 



B. -REPAIR TO DAMAGED KEEL — 




I, ^ •! ,| 

!• \ f(££iSOA/\ 

!; FfiuAfG V 8 



r/M3£W 



f y!^/////o| /^//jY////j ^^ 







M 



ff£eL :l 



c " w T •: 

\ cfOverAfL ^/ic£ I I, 




^/^<?/vP4.ar£ 



FlO. 223. 



keel to the bilge for a length of 12 to 15 in., and the stowage 
chocks made to suit. 

One usually finds plenty of paint on a boat after a few years' 
service, except in way of the chocks, the position where the need 
for protection is the greatest. 

Occasionally a stem or stempost becomes damaged, and can 
be repaired without the necessity of removing the associated 
combinations, by backing out the apron and deadwood fastenings, 
scarphing in a new stem and stempost-piece, and fitting an 
additional breasthook in way of the scarph. 

Local damage to a keel as a result of fouling some obstruction 
when launching the boat, or the opening out of a defective knot 



390 SHIPS' BOATS 

when the material has become seasoned, causing the boat to sag, 
may often occur. Fig. 223 b shows how the local weakness may be 
remedied, by fitting an iron plate xmder the keel, of sufficient 
length to take a nimiber of long screw bolts, having their nuts 
hove up on stout washers fitted to the keelson. 

The United States regulations insist that lifeboats shall be 
stripped, cleaned, thoroughly overhauled, and painted at least 
once in every year. 

Lifeboats which form part of the statutory equipment of a 
passenger vessel are periodically inspected by surveyors of the 
Board of Trade, who are also responsible for the survey of the 
steamer. 

The life-saving aj)pliance8 of all cargo vessels are liable to be 
inspected by the surveyors, whenever they come into a British 
port, whether the vessel is British or foreign-owned. It is 
considered that the present available staff of the Board of Trade 
is insufficient for the amount of oversight that is necessary for 
carrying out a proper and systematic survey. 

Much of the loose talk which one occasionally hears about the 
condition of ships' boats, is largely the result of a poor system 
of maintaining efficiency and periodical inspection by the officers 
who are held responsible for the upkeep of the apparatus. 

It is also difficult to maintain the constant interest of the crew 
on a cargo vessel in the condition of the boats and equipment, 
owing to the brevity of their stay on a j)articular ship. The 
system of signing (m crews for each voyage has its disadvantage 
in this respect. 

If only ordinary care is taken to maintain the boats in a clean 
condition ; the davits, with their associated gear, periodically 
worked, and the crews trained in the use and management of the 
life-saving equipment, the need for a more constant inspection 
would not be so necessary. 

The buoyancv-tanks should be removed at least every twelve 
months, and the planking of the boat thoroughly coated with 
paint of a good quality. 

When the boats come in for repair or annual survey, oppor- 
tunity should be taken to lemove the buoyancy- tanks and pass 
them through the water- tank for the usual test. 



PART VIII 

FIRE AND BOAT DRILLS 

In the foregoing chapters the question of the construction and 
equipment of ships' boats has been considered in some detail, 
but it is obvious that in addition to the high standard of con- 
struction and the efficient provision of suitable life-saving 
apparatus, it is very necessary that the officers and crew of 
passenger and cargo vessels shall be thoroughly trained in the 
proper handUng of the Hfeboats and rafts. 

The evidence of excited passengers, during the proceedings 
of official inquiries into the loss of merchant vessels, as a result 
of coUisioii, or explosion from torpedo attack, has often given a 
wrong impression to the " man in the street " as to what really 
took place during the operation of launching, so as to cause the 
boats to become unsea worthy. 

The loss of the steamships Titanic, Lasitania, Empress of 
Irekvnd, and FaUihd, together with their valuable complement of 
passengers and crews, caused the interest of the whole world to be 
centred on this all- important question of life-saving appliances. 

The subject of an adequate and compulsory training for 
seamen in the management and saihng of lifeboats, was keenly 
discussed during various inquiries, and the question has always 
been one of interesting debate among ships' officers, especially in 
view of the conditions under which the crews of the Mercantile 
Marine Service are signed on. 

In the majority of cases, the men do not join the ship until 
just before the vessel sails, and they may only remain on that 
vessel for the one voyage. There are, of course, exceptions to 
the general procedure, where passenger vessels are running con- 
stantly on a fixed route, but, generally speaking, there is very 
little incentive for seamen to specialise in this particular and 
important branch of their duties. 

With an ordinary tramp steamer carrying cargo, and without 
passengers, the majority of the crew are probably making only 



392 SHIPS' BOATS 

one voyage in the vessel, consequently, they are not keen to 
take a special interest in the upkeep of the life-saving equipment. 
Without the responsibility of making any special arrangements for 
the safety of passengers, the interest of the officers and crew in 
making suitable provision for their own safety, has often been 
lacking ; this is a matter of some surprise to those whose duty 
it is to see that the regulations are carried out. The recent 
submarine menace made a considerable difference to this feeling 
of apathy so often exhibited ; but it was surprising how quickly the 
seamen became used to their surroundings, and their attitude 
resolved itself into a condition of " familiarity breeding contempt.'* 

Various proposals have been made from time to time to create 
means for giving proper training and instruction to seamen, 
before they should be allowed to undertake the responsibility of 
managing ships' boats and vessels' life-saving equipment; this 
phase of the subject is outside the intended scope of the present 
treatise. 

The importance of the matter has been carefully discussed 
by various authorities, and in the Report of the Merchant 
Shipping Advisory Committee of 1914, the question of the manning 
of the boats was considered by the sub-committee dealing with 
the subject of the type and construction of open lifeboats, and the 
following resolution was approved by the majority : — 

" That the effective manning of all the boats carried on 
" passenger and emigrant vessels can only be secured by the 
" training and organising of the crew as a whole. If the crew 
** as a whole be so trained and organised, the boats can be 
** effectively manned if there are two efficient boat hands carried 
** for each of the boats carried under the davits, or immediately 
" available for attachment to the davits. Facilities should be 
** given to enable all hands to prove their competency as efficient 
** boat hands.'' 

The committee further considered, that if lascars could be 
trained as efficient boat hands they might be accepted as equal 
to white boat hands, provided that an officer or petty officer was 
present at the launching of each boat, to communicate the 
necessary orders to them. 

It was uenerallv considered bv the committee that the efficient 
training of passengers to take part in the boat drill was impossible, 
and that the safety of the passengers would be more effectively 
secured by tlie training and organisation of the members of the 
crew in their several duties, so that they could take charge of the 
passengers and direct them to the boats in a prompt and orderly 



FIRE AND BOAT DRILLS 



393 



maimer. It is thought by thd writer, however, that once, at 
least, on every oversea trip, the passengers ought to be asked to 
perform life-jacket and boat drill. 

The International Convention on Safety of Life at Sea have 
formulated regulations in connection with the manning of 
lifeboats and rafts for passenger vessels. 

The following notes have been taken from the Merchant 
Shipping (Convention) Act, 1914 : — 

There nmst be, for each boat or raft required, a minimum 
number of certified Ufeboatmen. The allocation of the certified 
lifeboatmen to each boat and raft remains within the discretion 
of the master, according to the circumstances. 

In order to obtain the special hfeboatman's certificate, the 
applicant must prove that he has been trained in all the operations 
connected with launching hfeboats and the use of oars, that he is 
acquainted with the practical handUng of the boats themselves, 
and further, that he is capable of imderstanding and answering 
the orders relative to lifeboat service. 

An officer, petty officer, or seaman, must be placed in charge 
of each boat or pontoon raft, and have in his possession the 
names of its crew, and must see that the men placed under his 
orders are acquainted with their several duties and stations. 

A man capable of working the motor must be assigned to each 
motor boat. 

One or more officers must be assigned to see that all the boats, 
pontoon rafts or other Ufe-saving appUances are at all times 
ready for use. 

The minimum number of lifeboatmen allocated to each 
lifeboat or raft is dependent on the carrying capacity of the latter, 
and is as follows :— 



Certified capacity of boat or raft. 



Minimum number of 
certified lifeboatmen. 



Lcsti than 61 persons . 
From 61 to 85 persons 
86 to 110 
„ 111 to 160 
161 to 210 



>» 



»t 



»» 



>» 



3 
4 
5 
6 

7 



And thereafter, one additional certified lifeboatman for each 
additional 50 persons. 

Musters of the crew at their boat stations, followed by boat 
drills, must be held at least once a fortnight, either in port or at 



2" 394 SfflPS" BOATS 

{ sea. An entry being made in the official log book of these drill 

or of the reasons why they could not be held. ^ 

Different groups of boats are to be used in turn at successi^ 
boat drills. The drills and inspections to be so arranged that tl 
crew thoroughly understand and are practised in the duties the 
have to perform, and that all the boats and pontoon rafts on tl 
ship with the gear appertaining to them are always ready f( 

4 1 immediate use. 

i! The muster list is to assign duties to the different members i 

the crew in connection with — 

(a) The closing of the watertight doors, valves, etc. 

li (b) The equipment of the boats and rafts generally. 

(c) The launching of the boats attached to davits. 

(d) The general prepamtion of the other boats and the ponton 
rafts. 

(e) The muster of the passengers. 
(/) The extinction of fire. 
The same nmster list is also to assign certain duties to tl 

members of the stewards' department, to enable them to contr< 
the passengers at a time of emergency. These duties are i 
follows : — 
* (a) Warning the passengers. 

(6) Seeing that the passenger's are dressed and put on the 

life-jackets in a proper manner, 
(c) Assembhng the passengers. 
I (d) Keeping order in the passages and on the stairways, an 

1 generally controlling the movements of the passengers. 

The regulations fornmlatcd by the Convention relative to tt 
j manning of boats and the necessity for certified lifeboatme 

j have akeady been embodied in the General Rules issued by tt 

- United States of America, wherein it is stated : — • 

j "By * certified lifeboatnian ' is meant any member of tl 

crew who holds a certificate of efficiency issued under ti 
authority of the Secretary of Commerce. 

" In order to obtain the special lifeboatman's certificate th 
applicant must prove to the satisfaction of an officer designate 
by the Secretary of Commerce that he has been trained in a 
the operations connected with launching lifeboats and th 
use of oars ; that he is acquainted with the practical handlin 
of the boats themselves ; and further, that he is capable ( 
understanding the orders relative to lifeboat service." 
When the crew joins a British ship, one of the first duti< 
devolving upon the executive staff is the allocation of evei 



^^1^ FlllE AND BOAT DRILLS 395 

member of tUe ship's compauj to one or otJier of the boata. In 
order to make this system very effective, moat of the 
passenger steamship companies arrange for each of the deck, 
stokehold, and steward departments, beiuj; furnished with a 
badge, bearing; the number of the boat to which he belongs. 

A miistcr list U then prepared, which shows clearly the names 
of all the crew, and details their various duties connected with 
the fire and boat drills, giving the particular boat to which they 
are attached. 

A copy of this Hst is placed iu a prominent position in the 
various departments, to assist all tlie niembois of the crew to 
become familiar with theii' various duties, and to enable them 
to quickly pick up their positions in case of disaster, and to 
prevent panic among the passengers. 

Several of the leading British shipping companies have been 
good enough to supply the writer with specimen muster lists, 
giving in full detail the various duties which are allocated to the 
officers and ciews, but no usefid purpose will be served in repro- 
ducing a list issued by any particular company. Each of these 
lists may differ in detail, but in substance they are i>ractically 
the same. 

The following notes will fjive tlie readLT a general idea of the 
various duties allotted to the memburs of the crew. 

Usually a plan of the boat stowage is indicated on the muster 
list, every boat being numbered with .large and distinct figures, 
odd numbers being on the starboard, even numbers on the port 
side. OroupB of boats, boata stowed one above the other, are 
also lettered A, B, C, etc., in addition to their number. 

Under each number and letter are shown the names of the 
various members of the crew who have been allocated to that 
particular boat. 

Various officers are selected to control the different groups of 
boats, and each boat's crew is divided into two companie,s, one 
consisting of six " station men," who take the following 
positions : — 

No. 1 Lower forward fall. 

No. 2 Clear away fall. 

No. 3 Lower after (all. 

No. 4 t'lear away fall. 

Nos. 5 and 6 . . . .in boat to attend to re;; 

leasing gear (one forward 
and one aft) 



396 SHIPS' BOATS 

the roinaiuder are " spare nieu," and will attend to any duties 
which may be given them by the officer in charge. 

The stewards are generally responsible for the provisioning of 
the boats, and acting in conjunction with the purser and chief 
stewaid, control the passengers below decks and assemble them 
in proper order at the various boat stations. 

" Man overboard " is usually notified by continuous short 
blasts on the steam whistle. . The emergency boats situated 
nearest to the bridge, one on each side of the vessel, are kept 
constantly rigged outboard in the davits, ready to be released 
at a moment's notite, with special faciUties provided for quickly 
getting into the boat, usually by fitting a net or rope ladders 
between the deck and boats. Immediately the signal is given, 
tlie watch on deck should at once man the lee emergency boat. 
The officer of the watch is responsible for these boats being at all 
times ready for use. 

On the fire alarm being sounded, or the order " Fire Stations " 
given, it is usual for the junior officer on watch to immediately 
proceed to the seat of the fire, collect the watch of seamen and 
other available men, and employ them to extinguish the fire. The 
second ofiicer remains on the bridge, the chief officer being in charge 
at the fire, and the first officer being in charge of all groups on deck. 
The stewards, purser, baggage master, etc., control the passengers 
and muster them at designated positions. The chief engineer 
and engineers on watch stay in the engine-room, the remainder of 
the engineers beinii; in charge of their pumps and groups on deck. 
The senior tele^^rapliist remains at his instruments, and the doctor 
in the surgery ready to attend injuries. 

Various members of the crew are detailed to attend with 
hoses and smoke hehnets, and to muster at the hydrants and 
extint^uishers, and be prepared to close bulkhead doors and side 
scuttles which are situated in their particular section. 

The details of the procedure coimected with both fire and boat 
drills are shown on the same muster list, as the latter is always 
associated with the former. 

Certahi oiiicers are held responsible for the necessary equip- 
ment and seaworthiness of the boats, and their dutv is to see that 
tliey are at all times ready for any emergency. The water- 
breakcMs in the boats must be kept constantly fiUed and properly 
hishctl down, bread tanks exaiiuned frequently , and the biscuits re- 
newed when necessary. Careful exammation is made of the davit 
lockings and boat furnishings ; the sliding chocks and swivels in the 
lower blocks should be oiled and worked at least once a week at sea. 



FIRE AND BOAT DRILLS 397 

Before a passenger or emigrant vessel leaves the home port, 
an inspection is made by the Board of Trade Surveyor, who 
satisfies himself that the lifeboats and their equipment are in 
good order and can be manned by efficient crews. Certain boats 
are selected, and these are swung out by the davits, lowered into 
the water, manned and exercised by their respective crews. 

Subject to suitable weather conditions, there is usually a 
daily boat drill of the deck hands, each watch being exercised 
on alternate days ; and at definite periods the whole crew are 
practised at fire and boat drills, which — ^in accordance with the 
latest regulations — must be at least once a fortnight. 

The necessity for frequent drills cannot be sufficiently 
emphasised. The success of the operation of any such scheme as 
briefly outlined, during a period when a heavy sea is running on 
a dark night, when the passengers are in a condition of nervous 
excitement, largely depends upon the organising power of the 
ship's officers, which can only be made perfect by constantly 
drilling the crews, and making the passengers accustomed to 
take up their positions in preparation for any emergency. 
The real difficulties can only be appreciated by those who 
have taken extended voyages to distant countries through 
troublesome waters. 

Very searching inquiries have been made from time to time 
into various shipping disasters, and it is to the honour and glory 
of the Mercantile Marine Service that officers and men have 
" played the game " when faced with disaster. They have always 
stood firmly at the position of duty — oftentimes at great personal 
disadvantage — exhibiting that spirit which has made the name 
of the British seaman to be honoured and admired by all peoples 
throughout the world. Safety for passengers has always been 
their first consideration, and it seems almost superfluous to print 
in conspicuous lettering on the muster list that women and 
children must first receive at^ntion. 

To carry out the instructions of the officers with smoothness, 
and avoid the creation of excitement or panic among the 
passengers, it is of paramount importance that drills should be 
constantly, and within definite periods, carried out on aU foreign- 
going passenger and emigrant vessels. Passengers must be 
organised and controlled. 

Irreparable damage can be done by excited individuals 
interfering with the launching of the boats and the duties of the 
crew. In many instances it has been proved that difficulties with 
the operating gear of the boats and davits have been traced 



398 SfflPS' BOATS 

directly to unthinking passengers manipulating the falls without 
the assistance of the recognised boat's crew. 

However, there are times when a feeling of apathy is some- 
times exhibited by the crew, which can only be explained from 
the fact that the men get accustomed to situations of danger, 
and it is, therefore, most essential that the oificers should maintain 
a strict enforcement of discipUne and a proper recognition of the 
regulations. The writer's own experience on one occasion when 
crossing the Atlantic is sufficient evidence to make it necessary 
to call attention to the fact, that boat drills are not always 
carried out as they are intended. The vessel left a British port 
for New York in a convoy which was attacked by submarines 
when two days out at sea. The passengers were never at any 
time during the voyage allotted to any particular boat, and were 
simply given instructions that at the given signal they were to 
meet in the saloon. The crew were never exercised at boat drill, 
but simply mustered on the seventh day out from port, at their 
respective boats ; it was the opinion of the writer that the 
majority of the men, judging by their attitude, were quite 
unacquainted with the necessary duties. 

Confidence is immediately created among the passengers, and 
confusion would be avoided should disaster overtake a vessel, if 
the regulations in regard to fire and boat drills were faithfully 
carried out by the ship's officers and crew at the recognised 
periods during a voyage. The incident previously referred to 
is only inserted to prove the necessity for a closer supervision to 
be exercised by the authorities, in maintaining strict recognition 
of the rules which are issued to safeguard the interests, not only 
of the passengers, but also those of the crew. 



PART IX 

WEIGHTS OF LIFEBOATS, EQUIPMENT, AND 

MATERIALS 

The scantlings of all material used in the construction of wooden 
lifeboats of Classes Ia and Ib are now practically standardised 
by the British Board of Trade, and it therefore becomes an 
easy matter to estimate the total dead load which must be sup- 
ported by the davits. 

So much latitude has hitherto been given to boatbuilders, owing 
to the absence of any detailed specification, that it became a matter 
of pure approximation to estimate the weight of boats ; ship- 
builders were, therefore, placed at a disadvantage when calcu- 
lating the sizes of davits, and the strength of their associated 
gear. 

TABLE XXVI. 
Weights of Details of Boats' Equipment. 



l>etnil of equipment. 



One gallon of oil in canister. 
Liquid binnacle coni£>a88 
Two hatchets .... 
Two-gallon iron bucket 

Iron baler 

Tool bag (canvas sides) 
Brass lantern .... 
Six -gallon water breaker 

(empty) 

Sea-anchor with tripping line 
( 'opper dipper .... 
Matches in W.T. Tin Box . 
Oil bag 



Weight 
In lbs. 



14 
9 

3i 
4 
2 
2 
3 



I2i 
13 

3 OZ8. 

2 ozs. 
8 OZS. 



*f 



*» 



»» 



9» 



t» 



»» 



Detail of eciulpment. 



Ash oars 13 ft. long 
14 ft. 
16 ft. 
„ „ 16 ft. 
Boat hook 
Painter 

Sails and covers vary for \ 
different boats. Those for i 
a boat 24 ft. in length . ! 
1 gallon of water in breaker 
Biscuits per person . 
Orutches (a set of 8) . 
Red lights in cannister . 



Weisht 
in lbs. 



15 
16 
17 
18 
5 
24 



30 

10 

2 

5 

5i 



Tlie writer lias weighed the various details of equipment as 
given in Table XXVI., and periodically checked the weights of the 



400 



SHIPS* BOATS 



boat« with the standard dimensions shown in Table XXVll. The 
particulars have been grouped togetiieo' in such a form as will 
enable the shipbuilders to readilv arrive at a veiy close estimate of 
the total weight coming on the davits. This informatioii will 
also assist patentees of special appliances designed to operate 
the launching of ships' boats. 

The difference m weight between steel and wooden lifeboats 
con8tract«d in Great Britain is now practically negligible. 



TABLE XXVII. 
DP WOODKK LlTSBOATS, CLASsn Ia a 



rameriBlnns. 


II 




1 

s 


30-0'x3'C' X3'75 


607 


2fl-0'x8-76'x3-6' 


546 


28-0'x8-5' x3-5' 


500 


27 0'x8-26'x3-4' 


454 



i 


1 

43-4 


1 


V 

GO 


1^ 


cwts. 
8S'4 


51 


391 


79-8 


50 


35-7 


73-7 


46 


32-4 


68-3 


40 


29'0 


68-9 


30 


281 


630 


32 


23-2 


47-2 


30 


214 


44-2 


20 


18a 


38-3 


23 


170 


33'9 



■s 

i' 

Cltt*. 

7-0 


s 


ill 


cwM. 
138'S 


■■a 


7-0 


1267 


129-0 


66 


ns-B 


no-o 


6-6 


106-2 


108-1 


6-0 


030 


96-6 


60 


86-1 


87-6 


50 


75-4 


77-6 


5fl 


70-6 


72-7 


4-8 


61-8 


63-5 


4-5 


564 


57-1 


4-0 


49-Q 


61-4 


3-5 


430 


44-3 



39-4 

34-6 
30-0 



The weights in Table XXVII. are based on latch being uaed 
for the planking. If teak is utihsed then the weight is increased 
by about three-quarters of a pound for every cubic foot of 
capacity (L X B X D X 0-6). 

It bet^omes somewhat difficult to state with any degree of 
accuracy the exact weight of the various kinds of timber used in 
the eniDttniction of ships' boats. Timber felled in the spring 



WEIGHTS OF LIFEBOATS, ETC. 



401 



contains more moisture than that felled in the winter. Moisture 
adds to the weight ; some trees when felled contain about 
40 per cent, of moisture, and during the process of seasoning this 
is reduced to about 15 per cent. The wider apart are the annual 
rings, the more sapwood is present, and consequently contain a 



greater amount of moisture. 



The list of materials given in Table XXVIII. will be a satis- 
factory guide for all practical purposes in boatbuilding. * 



TABLE XXVIII. 
Weights of Matebials. 



Material. 



Asb, English 

„ American 
Beech 
Birch 
Cedar 
Chestnut 
Cypress 
Elm, English 

„ Wych . 

„ Canadian 
Eir, Dantzic 

„ spruce . 
Greenheart 
Hickory 
Inarch 

Lignum Vita) 
Mahogany, Cuba 

Honduras 
Lagos 
Gaboon 
Maple 
Oak, English 

„ live 

„ white . 

„ African 
l*ino, red 

„ yellow 

,, long leaf 



»» 



«» 



»» 



Weight la 
lbs. per 
cub. ft. 



48 
40 
48 

4:7 

31 

3H 

30 

30 

38 

45 

30 

30 

70 

49 

39 

83 

48 

42 

40 

35 

49 

52 

59 

40 

02 

30 

30 

44 



»» 



Material. 



Pine, short leaf 

Oregon 

pitch 
„ white 
Plane tree . 
Redwood, Baltic 

„ California 
Sabicu . 
Teak ... 
Alaminium, cast^ 

„ sheet 

Brass . . . 
Cement, Portland 
Coal . . 
Copper . 
Cork 
Iron, cast . 

„ Mrrought 
Lead 
Leather 
Rubber 
Steel . . 
Tar, bituminous 
Water, fresh 
., river 
M salt 
Zino . . 

Balsa Wood (U.S.A.) 



Weight iu 
ibft. per 
cub. ft. 



38 

37 

40 

28 

40 

37 

20 

57 

53 
100 
108 
624 

73 

80 
548 
150 
450 
480 
712 

59 

58 
490 

75 
02-25 

03 

04 
445 
9-12 



Table XXIX. shows the weights of the occupants of 
boats based on the standard weight of one person being 
105 lbs. 

2 D 



402 



SHIPS' BOATS 



TABLE XXIX 

ViRUiHTi or PCBSOSS. 



-No. of 



2 



if 

7 

H 

•I 
II 

12 

i:{ 

17 
18 

h) 

20 



^'eloht In cwta. 


So. nt 
21 


Wdsht laevu. 


1 -4732 


30-94 


2'iiO 


22 


32-41 


4-42 


23 


33-88 


57*0 


24 


35-36 


7 37 


25 


36-83 


fi'Hi 


26 


38-30 


1031 


27 


30-78 


1 1 70 


2« 


41-25 


I3 2»i 


20 


42-72 


14 73 


:io 


44-20 


Wi21 


31 


45-67 


I7'*i>i 


32 


47 14 


loir, 


33 


48-62 


20(13 


:u 


50-00 


2210 


35 


51-56 


23'r>7 


30 


53-04 


2.'i-04 


37 


54-51 


2<ir>2 


38 


55-98 


27 Oil 


30 


57-46 


20-40 


40 


5803 



So. of 



41 
42 
43 
44 

45 
46 
47 

48 
49 
50 
51 
52 
53 
54 
55 
5<) 
57 
58 
59 
60 



lSO-40 
61-87 
63-35 
64-82 
66-29 
,67-77 
60-24 
70-71 
7219 
73-66 
7513 
76-61 
78-08 
79-55 
81-03 
S2*50 
33-97 
85*45 
86-92 
88-39 



PART X 

SECTION A.— BOAT STOWAGE AND TRANSPORTING 

ARRANGEMENTS 

One of the most important considerations dealt with by the 
shipbuilder and shipowner in working out the details of design 
for a large passenger vessel is the question of securing a practical 
arrangement on the boat deck, for dealing with the satisfactory 
stowage and speedy launching of the ship's lifeboats. 

The subject has riveted the attention of the general travelling 
public for many years, mainly as the result of several unfortunate 
and unavoidable disasters which have occurred to well-known 
ocean-going passenger vessels ; and to the increased faciUties 
provided during recent years for bringing the peoples of the 
United States of America, Canada, Great Britain, and the 
continental countries, into closer contact and with greater 
frequency. 

Royal Commissions, Departmental Committees, and an Inter- 
national Conference on Safety of Life at Sea — which included the 
best known authorities of all countries — ^have considered in great 
detail, all the diflSculties which surround the general question of 
equipping cargo and passenger vessels with the most practical 
and satisfactory appliances, to ensure in the future a larger 
measure of safety for both passengers and crews. 

The regulations made by the Board of Trade in regard to the 
stowage of boats, rafts, etc., and embodied in the Rules for 
Life-saving Appliances of 1914, are as follows : — 

** (1) All boats and rafts shall be stowed in such a way that, 
'' even under unfavourable conditions of list and trim, as large 
" a number of persons as possible may be embarked in them, and 
" that as large a number of the boats as possible shall be capable 
'' of being launched on either side of the ship. The additional 
" boats, or rafts, may be stowed in rows across a deck, bridge, 
" or poop, or approved appUances for transferring the boats, or 
" rafts, from one side of the deck to the other may be employed. 



" CI 

fl 

ii 
a 
a 



404 SHIPS' BOATS 

" (2) One or, if necessary, two of the additional lifeboats may 
" be stowed under the Ufeboats of Class I. attached to the davits. 

"' (3) Additional Ufeboats may be stowed in tiers of two or 
" three one above another, or they may be fitted one within 
" another, on condition that means are provided, to the satis- 
" faction of the Board of Trade, for readily attaching them to the 
** davits, and lowering them into the water. 

'"(4) Where a boat is stowed underneath another boat there 
" shall be provided approved removable supports or other 
*' approved appUances, so as to secure that the weight of a boat 
" is not unduly supported by the boat underneath it. 

(5) Boats may only be stowed on more than one deck on 
condition that proper measures are taken to prevent the boats 

*' from a lower deck being fouled by those from a deck above. 

(6) All other buoyant apparatus, lifebuoys and life-jackets 
shall be so stowed as to be readily available in case of 
emergency/' 

it has been clearly demonstrated in all disasters at sea how 
difficult it is, even in calm weather, to make full use of all the 
boats that are stowed on board. 

The necessity to provide " boats for all " is a problem of 
increasing importance, in view of the large number* of persons 
which are being carried on the modem passenger vessel. 

The *' raft " and *' buoyant apparatus " were very distinct 
and noticeable features of the equipment of all vessels sailing 
through the danger zone, during the recent piratical and devilish 
submarine war on merchant ships. It was impossible to provide 
actual seating accommodation in the available boats on a large 
number of the vessels transporting troops overseas, consequently 
great quantities of rafts, Hoats, etc., were carried in addition to 
the usual life-saving equipment. 

The destruction of the ship's boats caused by torpedoes and 
mines was so extensive that the necessity for large numbers of 
rafts is (j^uite apparent. 

In view of recent experience it seems almost essential to 
perinaneutly ecjuip all ocean-going vessels with a certain per- 
centa«.^e of rafts or buoyant apparatus, without weakening the 
present rules for boat stowage. 

Rafts whicli are of a convenient size for man-handling, are 
sufficient for an emergency, and which wall succour a nimnber of 
persons for even a few hours only, have often provided the means 
of sustaining life until reUef arrives from the ship's boats or from 
anotlier vessel in the immediate neighbourhood of the disaster. 




BOAT STOWAGE, 

To provide satisfactory means for stowing and handling the 
lar;j;e number of b()ata required by the Kules for Life-savinj; 
Appliances, it has been necessary to stow in tiers a laFj^e 
portion of the boats having collapsible bulwarks (Class II.). 
far, it lias been found practically impossible Ui atow all the life- 
boats within the sweep of the actual laimchiog and lowerinfj 
apparatus. It is therefore necessary to provide some mechamcal 
means of transporting the boats from the stowing to the laimching 
positions under the davits, or other lowering appliance. 

In case of disaster, the vessel would, in all probability, take a 
list, and it is therefore essential to make compiilaory— where 
boats are stowed inboard or across the deck — the fittinj; of some 
mechanical means in the form of transporting gear, that will be 
strong cnoiifjh and siifiicipntly effective, in bringing the boats from 
their stowing positions to the davits. 

It largely depends on the type of davit proposed to be fitter!, 
as to the most suitable arrangement of transporting ap|iaratuK. 

A feature in connection with the st^twajje of ships' boats 
which is often lost sight of by the shipowner, is the provision of 
suitable means of access to the interior of the boat for periodical 
ins|)ection. 

With the present arrangement of stowing pontoon lifeboats 
in a crowdej condition on the boat deck, and covered up with 
canvas, it is quito possible to imagine that the l>tiats are never 
inspected internally, except at the annual survey. 

The life nf a boat not only depends on the quality of the 
conetructioii — to which sufficient attention has already been 
given — but also upon the means which are adopted Ui maintain 
a aystoniatic inspection of the condition of the interior and extonor 
of tJie hull. The stowage should, therefore, be so arranged as to 
permit of easy access to each boat. 

The matter presents some difficulty, owing to the required 
number of boats ami the limited available space for stowage. 
A glance at the photograph in the frontispiece will give the reader 
some idea of the crowded condition of a boat deck. 

The Martin Patont Boat Transporter has been fitted tio a 
large number of well-known passenger vessels, including the 
Ai/uUtinm, Adriatic. Baltic, etc. 

Illustrations of the apparatus are given in Figs. 224. 22f) 
and -iafi. 

The transporter conaist.s of two carriers fitted with choclre 
to carry one or more lifeboats, tlie carriers being enpportetl on 
rollers which run on two trackways leading to the vessel's side. 



406 SHIPS" BOATS 

One roller of foch cftirier Is titled with pina which meaft iin 




225.^Tho " Mnrtin ", put^'nt boat transporter. Tractwaj-a stowed. 

correaponding holes in the tracks, these pinned rollers being 
connected together with a shaft. 





BOAT [STOWAGE, ETC. ' 



407 



By turning a crank which actuates a wurm gear, the shaft is 
revdivecl and the transporter is moved atliwartehip, bringing the 
boat from the inboard position to the davit for launching over- 
board. 

Throughout the process ot moving the boat, the apparatus 
is under full control bv the worm fi^arinf!, and the boat cannot 
take chart;e. 

As will be seen [from Figs. 224 and 225 the traekwaya can he 
hinged and stowed, leaving a clear passage on the deck each side 
of the boat. 

A very neat and effective transporter has also been designed 
by Mr. G. Tumhull. M.Inst.N.A.. of Messrs. Alfred Holt and Co., 
Ltd. Tlie arrangement does not call fur any 4'f*i*' description, 
for the various designs of transporters are very mueh ahke in 
principle, but differing in details. A feature in connection with 
this apparatus, which must appeal to every ship's officer, is the 
satisfactyr)' pnitcction which is given to the trackway, from the 
entrance of grit and dirt, enabling the transporter t*) be always 
in a condition for meeting an emergency. 

As will be seen from Fig. 227, the inboard boat was trans- 
ported and the mechanism operated by one man. The photo- 
graph shows the outer boat ready for lowering and the inner 
boat transported to the' outer position ready *<» be hooked on to 
the falls. 

It will be of general interest to state that in a vessel fitted with 
Tumbull's Patent Davit Turning Out Gear and Patent Trans- 
porter, during the official tests in Glasgow, the whole operation 
of lannching two Class I. bciats, sf-iwed abreast of one another, 
only occupied twelve minutes. This same vessel was torpedoed 
in the Atlantic, and all the passengers and crew were safely 
landed with thn boats. 

The Welin system of traversing boats from one side to another 
acoks t)J provide a way out ot the difficulty of inboard stowage. 

The outboard boats are provided with folding chocks, the 
inboard boats having fixed chocks of a simple construction, which 

also hinged. A trolley running on rails, operated by means 
of an endless wire, allows a free travel from one side of the ship 
to the other, and being self-locldnj?, obviates any danger of the 
boat taking charge. The. trolley itself is provided with two 
temporary lifting chocks, the arms of which are extended in such 
a way as to form levers, and by simply heaving on a small set of 
purchase blocks, these levers are brought together, lifting the boat 
(and holding it temporarily steady) sufficiently to clear the keel 



SHIPS' BOATS 




r 

I 




BOAT STOWAGE, ETC. 

over the other cliocks in their hinj^ed down position. Tlie boat 
may, therefore, be moved without hindrance from one side of 
the eliip to the other. The traversing standard ia deaigne<l to 
give greater power or gitiater speed according to circiiniatances. 

The same system may satisfactorily be modified to deal witli 
two boats, and a single-acting davit thereby installed instead of a 
double-acting, if desirable. 

The various systems have much to commend them to the 
favourable consideration of the shipowner, but the problem of 
boat transportation, when the vessel is heavily liste-d, is one of 
considerftble difficidty. more than thr iion-seiifaring r 
patra, and the success of any inst-allalion depend? 





Mi'lh'Hl of iiltir^: doiihlo m 



: I'hookrt. (InlHiiird nnd niillHinril.) 



simplicity, speed, and a trained erew for manipulation. It 
remains t« be seen in the future days of ship construction, whether 
the stowage arrangements can be impnived, for there is abundant 

I scope for the exercise of ahitity and ingenuity. 
The position of the supporting chocks ia at the quarter lengths 
of boat from sti'ni and st«nipost, This standard practice enables 
the b(}atbnilder to fit pad pieces on the wooden boats, or doublbig 
plates on the steel boat«, in way of the chocks. The pad jjii-ces 
protect the boat and simplify the construction of tlie chock. 
It is a matter of opinion as t« the desirability of having double 
or single chocks fitted at each end of the boat. It-largely depends 
on the type of davit fittwl. There is no doubt that the double 
chock {Fig. 228) gives bettor support to tlie boat, especially in 



I 






f! 



I 

f ; 

I 

. 



410 



SHIPS' BOATS 



view of the fact that the boats are well griped down to i 
deck on the unsupported side, where the single chock (Fig. 2i 
at each end is fitted. On the other hand, every facility shoi 
be ^iven to allow the boats to swing out quickly at an emergenc 
and it is possible where the outward chock is dispensed wil 
for the boat to be pushed outboard without being actually lift 
by the falls. It is considered preferable, in any case, whetfa 
inboard, or outboard and inboard chocks are fitted, that th 
should each be made to slide and hinge down, with the upp 
portion low enough to be below the top of the fixed deck choc 
to prevent dama<2;e from the keel of the boat, as shown 
elevation in Figs. 22!) and 281. 

It is necessary wlien fitting the inboanl and outboard choc 




Fig. 230. 



Fio. 2: 



Mcthcxl of iittini; sin^rh; stowingjchocks. Jnboard.J 



to arrani^'o for tlio fixed l)as(» to have a st^^p immediately in wi 
of the keol, as sliowu iu Fiir. 22S, to permit of the boat beir 
cjuickly swiin^ out in tlie davits without the necessity of usii 
the falls to lift the boat. 

A slidiuir chock is sometimes fitted as shown in Fiir. 281 a. tl 
s]i<lm«^' porticm l)ein<,' dovetailed into the fixed chock. Ti 
sclieme. however, is not recommended, as the weather tends t 
swell th(^ material and prevent easy manipulation. 

Messrs. Welin Davit and P^ngineering (Jo. have several pater 
st^)wage chocks. Two types are illustrated, the one in Fig. 28 
consists of an inner and an outer chock. The outer chocks ar 
hinged clear of the boat before launching by the aid of a releasin 
rod and a geared wlieel. By unscrewing the wheel and liftin 



BOAT STOWAGE, ETC. 



411 



it clear of the bracket attached to the inboard chock, the outer 
chock is pushed clear of the boat's keel. Patent gripes are so 
fitted that when the inboard slips are relieved the outboard gripes 
become disconnected at the same time. 

It is necessary that all gripes should be fitted with slips and 
hemp lashing, so that if difficulty is found with the slips the 
lashing can be cut asunder and the boat released. 

The second type of patent stowing chock is shown in detail 
in Fig. 288. The purpose of this design is to permit of the boats 
being stowed in a position to allow them to be partly outboard, 
ready for an emergency. An extreme inboard position is 
provided by the upi)er porticm of the chm^k sliding inboard. 



/'^ rf/vr c^/^£ 




SECTIONAL VIEW ELEVATION 

Fro. 232. — The " Welin " patent stowing chocks and gripPs. 

being secured to a deck plate by a clamp screw. The various 
details shown in the sketch are as follows : — 

A. Bracket attached to sUding chock to which the tumbler 
or keel rest is hinged. 

B. Tlie clamping deck plates for securing sliding chock in 
position. 

C. The clamping screw or eye-bolt for securing sliding chock 
to deck plates. 

D. The clamping tail piece attached to sHding chock. 

E. Tension rod connected to tumbler for relieving the keel 
of boat. 

F and G. Staple and pin to secure tension rod in position. 
H. Stopper plate limiting the sliding chock in its outboard 
position. 



SHIPS' BOATS 




■ PLAN, WITH X^NPTENaON-HOOWEMOVED - 



'LAN. wn-H Si-ioiHG C HOC K REM I 



a. 



d.. 



I''ni i(3,— Tlio ■■ Wfl 



It iiinj^le etou'ing chocka. 




BOAT STOWAGE, ETC. 



41S 



K. Guide baiu. 

L. Handgrips. 

M. Eye for taking boat's gripes, 

N. Securing bolt for tumbler, 

0. Timibler or keel rest. 

P. Securing bolta for bracket A. 

U. Countersunk bolts for tailpiece. 

X and Y. Sliding chock. 

Z. Fixed base. 

The position of the stowage diocks in I'elation to the davits 
should be such that the heads of the latter plumb the Ufting hooks 
in the boat. It is not an uncomtnon occurrence, in order to keep 
a wide passage between the lifeboats and raachinerj- casings, 
to find tiie lifeboats stowed outboard of a vertical line from the 
davit head, with the consequence that when the boats are .lifted 
after great difficulty, they swing inboard and are likely to injure 
persons in the vicinity. Satbfactory boat stowage should be 
arranged in the first place and the passage ways made to suit. 

There is a tendency with the shipbuilder of the ordinary 
cargo vessel to limit the overhang of the ordinary radial davits 
in order to save material, which results in the rubbers of the boat 
coming into contact, with the davit. Care must be exercised 
in planning the position of the davit head and heel in relation to 
the lifting hook, so that the weight of the boat, when the vessel 
is upright, practically enables it to swing out easily into the 
outboard position. The falls from the davit head to the lifting 
hook should be in a vertical hue throughout the operation, 
otherwise it needs extra power to push the boat out, which means 
that you practically have U> lift the boat in the falb to permit of 
clearing the davit«. A little prehminary care exercised in the 
drawing office with a paper plan model of the boat, will save a 
great deal of inconvenience and money to the shipbuilder. 

Wlien the vessel is upright there should be twelve inches 
clearance between the boat and the ship's side at the light water- 
line when the boat is lowered overboard. 

The ordinary cargo vessel of say 5500 try WXH) tons gmsa 
tf>nnage, carrying a crew of about sixty, usually has a boat deck 
extending out from the machinery casing to the ship's side, and 
situated thereon are one or two open lifeboate of Class 1. on each 
side. On the navigating bridge the two small Class III. boats are 
stowed under davits. When designing the boat arrangement. 
the platforms or boat deck should always be of sufficient length to 
permit members of the crew passing round the boat to make any 



414 SHIPS' BOATS 

adjustment to the davits, falls, or gripes, and thus obviate the 
necessity of climbing over the boats. 

One of the most important factors which governs the successful 
operation of launching a boat, is the efficiency of the lifting and 
lowering gear. The practice of simply taking ajtum round the 
davit with the fall when the boat is being lowerea into ihe water, 
in order to check the speed, is often responsible for accident. 
There should be a combined bollard and sheave at the heel of the 
davit as shown in Fig. 241, or a snatch block fitted as shown in 
Fig. 239. In each case the falls can be taken across the deck, 
which allows a number of men to speedily lift and easily control 
the boat and davits. 

Additional blocks or fairleads can be fitted to the deck, which 
will enable a lead to be taken to the winches, and faciUties thus 
provided for hauling up the boats on deck with the least amount 
of effort. ^ 

The question of getting the boats back speedily on board to 
their stowing positions is not of paramount importance, but it is 
an item which the chief officer is more than interested in, when 
boat drills are of such frequent occurrence. 

The relative value of the single wire purchase system compared 
with the multiple purchase is a much debated question. 

With a single wire rope the power required for manipulation 
is much greater. The clutches, brake gear, and the whole con- 
struction of the mechanism associated with the control gear miist 
be of heavy scantling, compared with the gear that is associated 
with a double or treble purchase system. 

Care should always be exercised when using new manilla 
falls, to stretch thcin well before they are rove through the blocks, 
afterwards taking the turns out and making the necessary 
adjustment at the beckct to ensure smooth working. 

The sizes of falls and blocks have been left to tiie opinion of 
the individual shipbuilder, in the absence of any particulars 
issued to guide him in this important i)ro vision. The \^Titer 
has a personal antipathy to wooden blocks. This opinion 
may not be shared by others, but these fittings are often 
of very doubtful design and inferior (juaUty, are very rarely 
tested, and quickly deteriorate. The cheeks have often been 
scored and even forced apart dining the operation of lowering 
the loaded boat for the first time, because the size and tj-pe were 
unsuitable for the purpose. You nuist have weight in the blocks 
to assist the falls, and this i)articularly applies to the non-toppling 
designs. The most successfid and useful design of blocks is 






BOAT STOWAGE, ETC. 



415 



conBidered by many men witli sea-going experience to be of 
m&lleable cast or wiuugbt iron. 

Where more than one boat is served by one set of davits it is 
moat essential that special provision should be made to prevent 
the lower blocks from " toppling," and the cables from becoming 
twisted, or what is termed " cable-laid." These difficulties 
cannot be avoided with the ordinary wood block when the falls 
are recovered quickly. To obviate the drawbacks associated with 
the ordinary block many devices have been patented and placed 
on the market. 

The Bulman Patent Boat Block .Syndicate of Great Eastern 




patent bout block. 



Street, London, have designed a special apparatus termed the 
" Bulman " Patent Lifeboat Lowering Gear, which consists of 
blocks made with the shell or frame extended vertically upwards 
and formed with a slot or opening extending right across the block 
above the sheaves. This opening is adapted to receive an end 
of a bar or rod, preferably rectangular in shape, and which 
extends across between the two lower blocks attached to the 
falls, and is thus adapted to prevent the blocks turning over 
(toppling), or the falls from twisting (cable-laid). 

In order that the spar or stroi^back can be easily detached, 
if found necessary, a patent tumbler arrangement on top of the 
block is fitted, which holds the spar securely in position, and at 



41C 



tlK- 



SHIPS' BOATS 
can bu speedily detached by liftjng the 



tumbler. 

-Vii ilhistnitiuii (.f the apparatus id jriven in Pig. 234. 

Several non-t">i>jiliiii.' blocks are now available for purchase, 
but vpn- few justify their description, for practically all of Uiem 
arc dependent ujnm ;;uide plates in some form or another, which 
do not in uiiv way iiiilitfy iir remove the inherent tendency of the 
block to topple, but mily prevent it from so toppling by guiding 
the falls at the expense of a certain amount of chafiiig. An 
illustration of the Weliii Patent Non-Toppling Block is given in 





diifij'i 
niilv 

bl.H'k 



hd .Ml- 
.'111 ]>[< 



. purl. 1 



- k..,>1 i, 
: tmi.-iL h 



M hr ]ii;«lr to I 
l.vk ilJld loi.kill- 



fiv.viii- fills in blocks. 

:!:)-1. Tlic principle ia veiy simple, the 
tliut the ceiit;ro sheave of tlie bottom 
nks uri' love in such a way that the 
■i lir.st over tlie raised sheave, so that 
■Mvs triiiisiiiittcd |.hniuj;h this sheave, the 
I (in ii|iH-lit condition, 
i; i;xcriisiil by the shipbuilder when reeving 
iiistiii'-iiiins arc issued by the Wehn Davit 
■V till' iiiiidaiice of sliipbuilders. Reference 
-. 'S-Wi. and from the position of standin>r 
iiilbniird ut the side of the block opposite 



BOAT STOWAGE, ETC. 417 

to the becket, the fall must always be rove from the inboard tread 
of the bottom sheave over the outboard tread of the top sheave. 
This will prevent twisting and chafing. Although contrary to 
accepted practice, these instructions are the outcome of experi- 
ments made by the firm, and the falls, with their particular 
blocks, must be rove as shown ; imless the quickest running part 
passes round the raised centre sheave of the bottom block, the 
efficiency of the whole gear will be entirely destroyed. 

/^jiother method of reeving manila falls through a treble 
purchase block is shown in Fig. 236. 

It is of interest in connection with this portion of the subject, 
to read from their report the recommendations of the Depart- 
mental Committee on Boats and Davits in 1913, in the case where 
more than two boats are served by one set of davits : — 

" (a) A gear must be fitted of sufficient power to turn the boat 
" out against a considerable list. 

" (6) There must be positive control in all positions. 

" (c) Wire falls should be used, and we recommend either a 
** single or gun tackle purchase. 

'* {d) The falls should be led to drums fitted with a powerful 
" and reliable hand brake for controlling the lowering of the 
" boat. 

'' {e) The winding gear must be so designed that it is possible 
" to adjust the trim of the boat, in order that if the vessel is down 
" by the head or the stem, the boat may be lowered into the 
** water on an even keel. This should apply to all cases in 
" which the winding gear is used. 

" (/) For hoisting the boat and recovering the falls rapidly, 
** there should be a quick-return geared hand- winch to which 
*' some system of power might, with advantage, be fitted as an 
" auxiUary. 

" {(j) If the tackles 'consist of more than a single part, some 
** approved type of non-toppling blocks should be fitted to prevent 
'' the falls from fouling when they are recovered. When the 
'' tackles consist of several parts, there is a serious risk that the 
'' lower blocks will capsize. Several types of blocks have been 
" designed which overcome this difficulty with varying success. 
** The simplest arrangement which we have seen is that of 
" weighting the lower blocks below the sheaves and carrying the 
" cheeks of the lower blocks above the top of the sheaves to 
** prevent toppling, and fitting a span between the blocks with a 
" weight in the centre to prevent the falls cable-laying. We 
*' think that this arrangement should prove quite satisfactory 

2 E 



418 SHIPS' BOATS 

'* with a gun-tackle purchase. It is probable that other types of 
** blocks exist, or will be devised, which will overcome this 
" difficulty. We refrain, therefore, from reconmiending any 
" particular type, but suggest that in cases where more than two 
'* boats are served by one set of davits, the Board of Trade ahould 
'' satisfy themselves that reliable non-toppling blocks are fitted." 

Special precautions shoidd alwa3rs be taken to stow the falls 
in such a way that they are ready for use, immediately the 
necessity arises. To simply dump them down into the boat or 
let them lie about the deck is to court disasteir. 

A number of passenger vessels are fitted with special barrels 
or tubs, into which the falls are coiled, but the general opinion is 
that the most serviceable and effective fitting b the reel. 

The majority of up-to-date passenger or emigrant veesels 
are fitted with emergency lighting apparatus, to enable the boat 
and promenade decks to be well lighted in case of accident to 
the ship's dynamos. Over each lowering station should be fitted 
a cluster of lights to facilitate the operation of launching the 
boats and embarking the passengers. The lighting system may 
be rendered inoperative by accident ; suitable hand lanterns 
. should be stowed in convenient positions as a means of guiding 
passengers to the boat stations. 

Complaint is sometimes received from ships' officers of the 
unreliability of tarred manila for use as davit falls ; instances 
have occurred when the boat has dropped at one end without 
the slightest warning being given by the appearance of the 
manila rope. The cause for the defect may have been in the 
method of treating the rope, but there is, nevertheless, a very big 
variation in the quality and price of manila rope falls, and it is a 
question for consideration whether it would not be advisable to 
enforce a limiting standard. Further reference is made to this 
subject in Part X., Section B. * 

During the rt^cent Jiubniarine menace each boat was suppUed 
with two painters, one being fitted with a strop and toggle, and 
the end led forward and kept belayed to a cleat or other suitable 
fitting fixed on the deck or bulwark. The purpose of this pro- 
vision was to enable the boat to be lowered into the water when 
the vessel was on the move, and permit the boatmen disengaging 
the lower blocks attached to the falls from the hooks in the 
lifeboat. 

This pro\ision is of special importance where the boats are 
stowed on the poop, the painters secured to the vessel prevent 
them coming into contact with the propellers. 



BOAT STOWAGE, ETC. 419 

It is sometimes necessary to stow the lifeboats at such a 
height as will enable them to swing clear of a fixed bulwark, in 
which case a simple chock and standard made up from plates and 
angles, as illustrated in Fig. 242, is a useful and serviceable 
fitting. The photograph incidentally shows TumbuU's Patent 
Davit Tuming-out Gear fitted to a socket-davit. 

The same measure of safety should be given to the crews of 
cargo vessels as in passenger ships. Insuiiicient care and atten- 
tion are often displayed in treating all the considerations con- 
nected with the life-saving appUances of an ordinary cargo vessel. 
The davits and boats are installed at a very late period during 
the construction of the ship, the davits rigged and the details of 
equipment supplied at the last moment — often when the vessel 
is loading her cargo — giving inadequate opportunity for the 
surveyor to have all the boats swung out in the davits and lowered 
into the water. 

The question of suitably providing stowage for the lifeboat of 
some of the small Home Trade vessels which cannot be equipped 
with davits, is often overlooked and inadequately dealt with. 
Vessels which proceed outside the smooth water Umits occasion- 
ally run into heavy weather, e.g, the passage between the Clyde 
ports and Belfast is very difficult at times for a large vessel to 
safely negotiate. Effective arrangements should, therefore, be 
made for the launching of the hfeboat. 

A typical arrangement is shown in Fig. 237, where portable 
stowing chocks are fitted to a cross-piece and attached to 
stanchions. The cross-piece takes the weight of the boat off the 
hatches. The derrick is stowed at a height that will enable 
the boat to be launched without the necessity to top the former. 
Suitable guy ropes and cleats are fitted to control the operation 
of launching. A wire bridle with shackles and hook are kept 
in the boat and attached to the lifting-gear on the derrick. 

A modification of this arrangement can be made to suit the 
requirements of most of these small vessels, and where a derrick 
is not available, the lifting-gear can be operated by the provision 
of a berthon and tackle from the rigging. The main consideration 
is to be able to laimch the boat on either side of the vessel without 
much effort to lift it from the stowage chocks and over the 
bulwark. To simply stow the boat on tiie hatches, lash it down 
to ring bolts, and rely on man-power to push it overboard, is 
considered inadequate and dangerous. 

An important portion of the life-saving equipment of all 
ocean-going passenger vessels, is the provision of suitable rope 



420 



SHIPS' BOATS 



ladders, stowed in convenient positions around the boat stat 
securely fixed to the bulwark or ship's side and coiled up in si 



OMfUff - 




W 



'T 





DETAILS OF - 




CHOCKS etc. 




* 




• A >. 


. . • _ . - . 




r'-EVATION - 



! 



: I 



^^----l^- 



\ 



I "I _ — 1 ^ I 



^\^-H- ~{r 



fitAi.'V ^/»'£-/y 






Ki.j. L\r 



PLAN 

(Jon«^r.»l nrransr«Miuut t.f lM»at ^towapo f«>r a small coastipg etea 



luaniior \\\\\\ tliov can bo (iiiiiklv ami oasilv lot down to the wa 
lino. This provision is of paitioular importance where rafts 
buoyant apparatus aro carrioil on boanl. 



ROUND BAR RADIAL DAVITS 421 

It has been suggested that it would be an advantage in large 
passenger steamers to stow the boats on two decks, but it is 
considered that great difficulty would result in the confusion of 
orders given to the boats' crews, and there would be great risk 
of the upper boats being launched before the lower ones were 
clear of the ship's side. 

SECTION B.— ROUND BAR RADIAL DAVITS 

A NUMBER of articles have been jnitten from time to time in 
marine magazines as to the relative value of ordinary radial 
davits compared with the mechanical davit, crane, or other 
patent launching apparatus. In the majority of cases one cannot 
fail to discover that these descriptions have been more or less 
inspired by the particular persons financially interested in the 
special devices designed to operate the launching of ships' boats. 
Each patentee claims to have solved all the difficulties associated 
with this much-debated subject. 

There are sources of weakness and disadvantage associated 
with almost every design of launching apparatus, but each type 
possesses some distinctive feature which appeals to the individual 
and finds favour with the shipbuilder and shipowner. No 
particular standard gear is recognised by the Board of Trade, 
and provided the proposed apparatus fulfils all the requirements 
of the regulations and successfully stands the prescribed tests, 
the Board of Trade give every assistance for that device to be 
fitted on a vessel as a part of the statutory equipment. 

To absolutely condemn the principle of the ordinary round 
tar radial davit is not justified by general experience. There 
are certain well known limitations to this type of davit, especially 
when operating the large number of boats now carried on passenger 
and emigrant ships. Many patent devices have been designed 
to mini m ise the drawbacks associated with the ordinary davit, 
but owing to the ease with which the latter can be manufactured 
by the shipbuilder on his own premises, and the relative advantage 
in cost of production as compared with patent apparatus, together 
with the seamen's long association with the manipulation of this 
type of davit, it is suggested that it will take some lengthy period 
before they will be completely replaced on ocean-going cargo 
steamships. 

One of the difficulties which is always associated with 
the operation of launching the boats overboard, is that during the 
process of lowering, the boat is free to swing transversely with the 



422 SHIPS' BOATS 

risk of coming violently into contact with the ship's side. Many 
devices have been suggested on various occasions to lessen the 
danger to the occupants of the boat. The fitting of ropes or 
jackstays to the ship's side for guiding the boats to the water- 
level, is considered objectionable and dangerous, especially 
when the vessel is rolling heavily, as there would be the serious 
possibiUty of swamping the boat. 

In any case, there must be adequate provision made for keeping 
the boats close to the ship's side from the time the lowering 
operation is commenced until Ae boat reaches the deck or position 
from which the passengers are embarked. 

It is advisable to arrange for the passengers to be embarked 
on the lowest open deck. The boat deck should only be available 
for the crew who are operating the launching apparatus. The 
rush of passengers into tl^e boats and interfering with the gear, 
has been responsible for accidents which have often been attri- 
buted to the inefficiency of the crew and the bad condition of 
boats and launching gear. 

Freedom for operation is an absolute necessity in case of panic 
and disaster. 

General Rule 13 of the Rules for Life-saving AppUances of 
1914 stipulates requirements which must be carried out in equip- 
ping vessels with apparatus for launching ships' boats. They are 
as follows : — 

Appliuncesfor lowering Boats, 



(C 

cc 



a 



(1) The davits shall be of approved form and fitted on one 
or more of the decks in such positions that the boats can b^ 
efficiently lowered from tliem, and shall be so spaced and placed 
" that the boats can be swimg out with facihty. Davits shall 
not be fitted in the bows of a ship, but they may be fitted in 
any other position in the ship, provided that the boats are not 
brouglit into dangerous proximity to a propeller at the time of 
'' launching. 

" (2) The davits, falls, blocks, and all other gear required 
** for lowering the boats, shall be of sufficient strength to the 
'* satisfaction of the Board of Trade, and in the case of foreign- 
* going passenger steamers launched on or after the 1st March, 
" 1913, they shall be such that the boats can be lowered safely 
" with the full complement of persons and equipment, the ship 
" being assumed to have a list of 15 degrees. 

(3) In the case of foreign-going passenger steamers launched 
on or after the 1st July, 1914, the davits shall be fitted with a 






ROUND BAR RADIAL DAVITS 423 




- ELEVATION — 



Fio L'n><. — Oencial a 





c-'JJr.. 


— V-f 


'" 


Tli^:«?« 


":3:. 


: 


J:!::--,- 


::%:, 


X 




'''"m 


■::i==^ 




.'r' /*?-" 


/> 


\ 


^ 










/r / 


"'."/. 






,..«., 


■ 


^,^ 




^r-7 


J^*^^ 


•--•_3^ 












-4*^ 




_ 








,J_;^tf^*^ 0"—"f-«' 














imctaa 




«™™ «roMr,rs 




i-a- 





- P I- ft N — 

of boot stowage for a 24-ft. Ctaaa Ia lifeboftt. 



424 SHIPS' BOATS 






(i 



gear of sufficient power to ensure that the boat can be turned 
out against the maximum list under which the lowering of the 
" boats is possible on the vessel on which they are fitted. 

" (4) The boat's falls shall be long enough to lower the boat 
" into the water with safety when the vessel is light. Life-lines 
'* shall be fitted to the davit spans, and shall be long enough to 
" reach the water when the vessel is light. Hooks shall not be 
" attached to the lower tackle blocks. 

(5) Means shall be provided for speedily, but not necessarily 
simultaneously or automatically, detaching the boats from the 

'' falls ; the boats placed under davits shall be attached to the 
" falls and kept ready for service ; the points of attachment 
of the boats to the falls shall be sufficiently away from the ends 
of the boats to ensure their being easily swimg clear of the 
davits ; the boats' chocks shall be of such construction and 
arrangement as shall be satisfactory to the Board of Trade. 

(6) Where more boats than one are served by the same set 
of davits, there shall be provided an approved appUance for 
lowering the boats in turn and rapidly, and arrangements ahsAl 
be made to prevent the falls fouling when they are recovered. 

(7) The Board of Trade may accept in Ueu of davits or sets 
of davits any other appliance, appliances, or arrangements, 
whicli appear to them at least as effective as davits for placing 
the boats in the water." 



(( 
(< 
(( 

i( 
(( 
(( 
(< 

<< 
(i 
<( 
(( 



For the ordinary radial davits to be effective and serve the 
purpose for which they are intended, they must be fitted on the 
vessel with care and forethought as to the actual requirements. 
The davits should be placed at such a distance apart as will allow 
the boat to swing out smoothly and easily, with the falls always 
hanging plumb. 

The relative positions of the head of the davit and the collars 
or deck sockets can be easily fixed in the drawing office with 
the aid of paper moulds. It frequently occurs when inspecting 
the life-saving appUances of a new ship to find that the boat has 
to be lifted at certain positions when swinging out the davits, 
in addition to being pushed out, in order to reach the outboard 
position. A httle preparatory work in the office would have 
obviated the difficulty. 

A typical boat stowage arrangement is given in Figs. 288 and 240. 
The length of the boat is 24 ft., the distance between the davit 
centres is 21 ft., and that between the davit heads is 18 ft. 9 in. 
The position of the hfting hooks would therefore be 2 ft. 7J in. 



ROUND BAR RADIAL DAVITS 



from the intersection of the outside of the planking with the 
stem, Btempost, or after edge of transom, as the case may he. 




Fio. 239. — Bound bar radial davits for » 24-f(. Class 1^ lifobont. 



A common practice is to weld a thumb cleat on the davit to 
take the load of the fall from the upper block and allow the boat to 



4S0 



SHIPS* BOATS 



swing clear of the falls when launching outboard. It is geneiaD]^ 
coiuidered that this fitting is daogeroas and should be condemned. 

The boat cannot be Tsised from the chocks with the fall 
nimung over the cleat, consequently when the former is lifted 
clear it becomes neceasaiy to temporarily laah the falls between 
tlie two blocks, to allow the lead to be replaced over the thumb 
cleat and carried down to the belaying cleat, bollard, or snatch 
block. 

The clump block fitted at the throat of the davit acting in 
conjunction with a snatch block at the heel, or a combiued 
bollard and sheave as illustrated in Figs. '24U and '241, is a more 
serviceable and satisfactoTy arrangement. 

Single wire guy ropes are usually fitted to the davits on cargo 
vessels, but the practice is not recommended and should be 
replaced by gun-tackle purchases, as being a more reliable 
method of controUing the da^-ita when launching the boats into 
the outboard position. 

At least four life-lines should be seized to the span between 
the heads of the davits on all passenger vessels ; the length of 
the linos must be sufficient to reach the hgbt water-line. 

It is very essential that particular care be taken to have t 
hole in the head of the davit, which takes the swivel bolt of t 
upper block, in a true vertical plane. The operation is usual 
undertaken when the davit is being forged on the slab in \ 
shipyard. The slightest amoimt out of the vertical will cam 
friction and prevent the boat swinging out easily. 

The securing nut to the swivel bolt must be recessed, as ahowi 
in Fig. 239, to enable a proper bearing being taken on the davj 
and not on the spectacle which is connected to the spar and g 
ropes. Attention should always be given to these fittings to a 
that they work smoothly and do not jamb. 

The socket-davit has long been considered out of date a 
ine£Gcient. Yet its vae is often permitted, and the combinstioi 
fitted as a part of the statutory equipment of out i 
vessels. 

There is one serious limitation to the radial davit, under 1i 
present requirements of the Kules for Life-saving Appliai 
It is unable to launch a boat over the ship's side against a li 
imless it is operated with a mechanical turning out or sluing geaS 

The British regulations do not insist on a mechanically-operate 
davit being fitted to the ordinary cargo vessel, because suffida 
soaring accommodation is provided in the boats, on either side Q 
the vessel, for the total number of persons on board. 




ROUND BAR RADIAL DAVITS 



427 



In a f oreign'-gomg p'assenger vessel, i.e. a vessel canying fnore 
than twelve passengers, the davits must be designed to allow the 
boats to be launched under the condition when the vessel is 



titS^€crAct£ pukre. 



9'DfM: OUAOROPLE SHCA^eO 

)rttWT. Iron Block 



S/s MACULA FALLS 



B'0/Arff£BL£ SH£A¥£D 

3lo€m 




Fiu. 240. — Round bar radial davits for a 28-ft. Class Ia lifeboat. 



assumed to have a list of 15 degrees, the boat being loaded with 
the full number of persons and details of equipment. 

lllustratioAs of^a mechanical apparatus designed for operating 



428 




SHIPS' BOATS 



ordinary radial davits against a heavy list, are ^ven in . 
2-21 and '241. The latter shows (he details of the worm 
and screw gear attached to the davit at the deck level. This 
mechaniam ia the invention of Mr. Georj-e Tumbull, M.I.N. A., 
of the firm of Me.'wrs. Alfred Holt & Co., Ltd., and has been fitted 
to quite a number of passenger vessels now in service. The saine 
type of gear can be fitted to socket-davits, where the boat i 
launched over stanchions and fixed guard rails at the ship's sid] 
Such an arrangement is illustrated in Fig, 242. 




Several other gears have been approved by the Board i 
Trade and adopted by a number of shipowners. 

The Pett's Patent Davit Tuming-out Grear is controlled by d)1^ 
Quixo Davit Co, of Ixandon, and is very similar in principle t 
the Tumbull patent. The Peninsular and Oriental Ste 
Navigation Company has recently installed one of their late 
passenger vesseb with the Quixo Davit Co. s apparatus. 

The Welin Davit and Engineering Co. have patented i 
arrangement which is operated by a wire rope control, called t 
"planet system," and is designed expressly for mampu) 



ROUND BAR RADIAL DAVITS 



429 



ordinary round bar davits and turning them outboard against 
a vessel's list. 

It is false economy to nip down the overhang of the davit 
to the lowest limits in order to save weight of material and cheaper 
production. When the boat is launched overboard there must 
be at least 12 inrhea clearance fit thi- Iil'Iu w;itcr-line, between 




Fio- 243,— Turnljiill' 



t^e boat and the ship's side, the vessel being In an uprij^hl 
position. The height of the head of the davit above th' 
support of ihe boat deck, should be such that when the 
is stowed in the chocks, there will be a distance of at ]f 
blocks between the lower and upper fall blof^l ' 
should allow the boat to be raised clear c' 
becomes impossible to hinge the latter do 



430 



SHIPS' BOATS 



Particular attention must be given to the method of securing 
the collars and heel sockets, sufficient riveting being arranged 
to maintain an efficient connection to the hull of the 'vessel, 
especially in view of the stress exerted on the davit when the 
vessel is rolling heavily in a seaway. 



TABLE XXX. 
Approximate Weight and Strength of Standard Quality Manila Ropk.* 



Dlam. 


Diam. 


Clr. 


1 

Clr. 


Approx. length 

of manlla rope 

in lib. 


Approx. weight 
and length of ooil. 


Approx. 

3.S. 
borne by 


Ins. 


mm. 


Ins. 


mm. 








i 


maaUa 








1 

1 ' 

12-7 


Ft. 

m 


In. 


Lbs. 
35 


Ft. 

1 


rope. 

lG. 


i"< 


4-8 


i 


1 
2100 , 


550 


i 


«>-3 


i 


19 


66 




50 


2750 


620 


A 


8 


1 


25-4 


41 




55 


2250 


1,000 


i 


10 


U 


28-5 


27 


■ 


60 


1620 


1,276 


■i 


11 i 


ij 


32 


IS 




70 


1260 


1,875 


12-7 1 


li 


38 


13 


4 


90 


1200 


2,400 


1 


1** i 


n 


44-4 


9 


7 


126 


1200 


3,300 


16 i 


2 


50-8 


7 


() 


160 


1200 


4,000 


2 


19 


h 


57 


6 


1 


198 


1200 


4,700 


H 


2or» 


n 


03-5 


r> 


1 


234 


120(h 


5.600 


1 
H 


22 


'11 


70 


4 


5 


270 


1200 


6,600 


1 


25-4 1 


3 


76 


3 


8 


324 


1200 


7,500 


W^ 


27 


H 


82-5 


3 


2 


378 


1200 


8,900 


»i 


28-5 


3J 


88-9 


2 


9 


432 


1200 


10,500 


n 


:u-7 


n 


95 


2 


5 


504 


1200 


12,500 


^h 


33 


4 


101-6 


2 


1 


576 


1200 


14.000 


n 


35 


H 


lUS 


1 


10 


()48 


1200 


15.400 


n 


38 


4.V 


114 


1 


8 


720 


i200 


17,000 


1 K 


390 


4] 


120-6 


1 


6 


810 


1200 


18,400 


41 


5 


127 


1 


4 


900 


1200 


20,000 


n 


44 


5^ 


140 


1 


1 1 


1080 


1200 


25,000 


•> 


50-8 


() 


l.'>2 


- - 


i 11 


1296 


1200 


30,000 




-){ 


oi 


1 65 


— 


, n 


1512 


1200 


33,iH)0 




57 


7 


17S 


— 


; 8 


1764 


1200 


37,000 


n 


<)3-5 


'h 


190-5 




7 


2016 


i200 


43,000 




(W)-7 


8 


203 


— 


' H 


2304 


1200 


50,000 


u 


73 


H\ 


216 


-- 


\ ^^ 


2590 


1200 


56,000 


:i 


7t> 


\) 


228-6 


— 


^ 


2915 


1200 


62,000 


3i 


79 


9.1 


241 


- 


' H 


3240 


1200 


68,000 


31 


H2-5 


lo" 


2.">4 


-— 


4 


3600 


1200 


75,000 



The weight and strengtli of manila rope per table, is approximate and may 
vary slightly either waj. Manila and sisal standard rope will weigh about 
alike. Jn the lower grades of manila and sisal there are greater variations in 
weight and strength, according to quality. Four (4) strand rope weighs from 
5 per cent, to 7 per cent. heavi(T than three (3) strand plain laid rope. Manila 
rope runs approximately 25 per cent, stronger than sisal. 



Supplied by the Waterbury Company, New York. 



ROUND BAR RADIAL DAVITS 431 

The emergency lifeboats are carried outboard and near the 
bridge, during the whole of the voyage at sea, and maintained in 
a position of security by fitting pudding fenders attached to the 
davits (See Figs. 238 and '240), die boat being hauled close in to 
the fenders by canvas griping bands, Ordinary rope lashings 
are not recommended in place of the griping bands, as the continual 
rolling of the ship produces too much friction between the rope 
and boat planking, with detrimental eSect to the latter. 

In arranging the size and pattern of blocks, due regard should 
be paid to the standard of strength, or factor of safety, recognised 
by the Board of Trade in connection with details of davit 
equipment. 

It JB anticipated that regulations will soon be in operation 
whereby detailed information will become available for the use 
of the shipbuilder to fix the sizes of the blocks and associated 
fittings. 

The writer has often heard complainta from ships' officers 
as to the unreliability of tarred hemp for davit falls. The action 
of the weather is often rLwpcjnsible for the sudden collapse of the 
falls without giving pre\'iou3 warning or any visible indication 
of weakness. 

The working load of manila rope is usually about one-fifth 
of the breaking stress. All blocks should be fitted with patent 
roller sheaves. Manila is stronger than tarred hemp. Ordinary 
hemp rope, unless it is tarred, quickly deteriorates when exposed 
to the weather; the effect of tarring, however, reduces its 
strength. 

Manila hemp is obtained from a species of wild plantain be- 
longing to the banana family, and grows in the Philippine Islands. 
The fibre is silky and lustrous in appearance and very tenacious, 
but light in weight. The strength and weight of manila rope is 
shown in Table XXX. 

The usual practice is to fit wooden blocks when serving 
manila falls, and iron blocks for wire rope. General experience 
has proved it an advantage to have iron non-toppling blocks 
instead of blocks made of wood, for the weight of the former 
assists the block in preventing it from turning over when recover- 
ing the falls. 

Special patient roller sheaves are very r d it is an 

added advantage to bush the sheave pin? ion. 

The becket is secured to tb* ck, the 

purpose of which is to liok imble 

attached to the standing j uper 



432 



SHIPS' BOATS 



block is fitted with treble sheaves, and the lower block with 
double sheaves, then the becket is fitted on the lower block, but 
when the upper and lower blocks are fitted with the same nambei 
of sheaves, then the becket is fitted on the upper block. 



TABLE XXXI. 
FiBBE-CLAD Wire Hoisttno Rope, Cruotblk Cast Btkel. 
Composed of five strands and a hemp centre. Nineteen wires to the stimnd 



IMamet^r 

in Inches 

before 

»erviDg. 



Approx. 

diameter 

after 

serving with 

marUne. 



Appro X. 
circumfer- 
ence aft€r 
serving with 

marline. 



Approx. 

breaking 
load m 
tons of 

2000 lbs. 



Allowable 

working 

load in 

tons of 

2000 lbs. 



Minimum 

sixeof drum 

or sheave 

in feet. 



Approx 



per foot 
inlbe. 



1 

I 
If, 

•♦ 
<* 

M 

I 

7 
H 

I 

u 



9 

10 



4 



u 
111 



I.', 

1.' 

12 






u 

2 

21 

9 3 

*'H 

:u 

•J 7 

5A 

.'->; 



2-2 
3 1 

4-8 
«-5 
8-4 

100 

12-5 

17-5 

23 

30 

38 

47 

5(> 

04 

72 

85 



0-44 
0-62 
0-96 
1-30 
1-68 
200 
2-50 
3T)0 
4H0 
HOO 
7(>0 
9-4 

11(> 

12-8 

14-4 

170 



i 

1 

U 

H 

n 
^ 

3 

3J 

4 

— 5 
5i 
5} 

7i 



•21 

•26 
•36 
•40 
•49 
60 
•80 
112 
1-29 

1 -mi 

2-07 
2^52 
3 06 
3-60 
419 
4-88 



Before reeving the falls tliey sliould be carefully stretched ; 
and after reeving, tlie shackle attached to the becket should 
be dis(;(»nnected and the turns taken out of the falls before 
re])lacing. 

Tiie Board of Trade have issued instructions to the effect, 
that in order to provide for speedily detaching the falls by hand 
when tlie boat is waterbome, all lower fall blocks are to be fitted 
with a suitable ring or long link for attachment to the sUng 
hooks fitted in the boat, unless some approved form of disen- 
gaging gear is adopted. Tlie eye on the block and the ring or 
link ar(» to be sucli as to provide a factor of safety of at least 
four, with a dead working load equivalent to the total weight of 
boat, e(|uipnient, and full complement of persons. 

The following extract has been suppUed by the Waterbury 
Company of New York, Chicago, etc. 



ROUND BAR RADIAL DAVITS 433 

Notes on Use and Care of Rope. 

Deterioration in rope is both mechanical and chemical : first, 
due to surface wear or from friction between fibres ; secondly, 
from exposure to weather and acids. Surface wear on ropes 
hkewise follows wtere worked through blocks or where sheave 
holes are too small for easy clearance or where blocks become 
fouled, causing improper alignment, the result of which is chafing 
of the rope. 

Ropes swell to some extent after being wet. Blocks with 
large enough sheave grooves should be used to take care of swell. 
Unlike metal and other similar substances, fibre rope has not a 
permanent elastic limit in which it may be worked indefinitely 
without injury. Owing to the tendency of the fibres to slip one 
upon another, the rope gradually loses its cohesion imder the 
repetition of very moderate tension, and may be seriously weakened 
by constantly working. If fibre rope is subjected to a sudden 
stress or even to a stress approaching that of breaking, its 
strengtli is permanently reduced, and it may be expected to give 
way under a ver\' moderate pull. Hence it is advisable to allow 
for liberal factors of safety, both as to working and breaking 
strains. 

Internal friction between the fibres increases to some extent 
when the rope is worked over a sheave. This ultimately has a 
tendency to break up the fibres, which also suffer a loss of vitality 
through heat caused by friction. The smaller the diameter of 
sheave in this connection the greater the friction. The use of 
sheaves of the largest diameter permissible is advisable, likewise 
rope, as the ultimate results will justify. 

AU rope should be kept clean and free from sand, mud, or other 
matter containing grit. Chemical deterioration from rotting, or 
termed by some " dry rot," generally increases through rope 
becoming water-logged and not given an opportunity to dry 
out in the open air. Allow the rope to dry naturally. Do not 
cover or prevent drainage as it retards the drying out process. 

When dragging rope over the ground it weakens the roi^^ 
and dirt and grit are picked up which grind in when the if 
used again. Unnecessary surface wear often occurs with ho 
machinery by contact against iron beams or the edges of i 
blocks. In transmission the surface friction rope agaiiu 
sheave also wears it, but the wear is ina "^n 

with that of a poor installation. 

Be careful in storing your rope 



434 SHIPS' BOATS 

commercial acids, which have a particularly injurious effect oi 

the fibre. 

Always use the largest rope permissible, as the limit of safety oi 
small rope is reached quickly. Inspect ropes frequently anc 
replace before the Umit of ssiety is reached. Loss of strengtl 
from heat or rotting is difficult to note except following test o: 
fibre. Internal wear can only be judged after careful inspection 
Large ropes do lose strength through rotting as quickly as th< 
small ones. 

Extreme tension occurs frequently in slings bending ovei 
sharp comers while under load. This breaks the fibres on the 
outer side while the sharp comers cut the ones on the inner side. 
To secure the best service from slings, sharp bends over un}'ieldino 
surfaces must be avoided and the load" should be considerablv 
less than the tensile strength of the rope. 

Running rope should never be allowed to touch anything but 
the wheels or sheaves upon which it works, neither should the 
rope chafe against the side of grooves of the wheels. Avoid 
vibration and slipping of ropes as far as possible. 

Be careful to have sheaves accurately balanced and in perfect 
ahgnment, otherwise rope is liable to jerk, chafe, and destroy itself. 

Manila, when dry, contains a small percentage of moisture, 
but will absorb as much as 30 to 40 per cent, in a damp atmosphere. 
Moisture does not tend to promote decay. In hot, dry weather, 
an occasional wetting of the rope will aid it. A freezing temper- 
ature renders the fibres brittle. 

Four-strand rope will weigii from 5 to 7 per cent, heavier than 
3 -strand rope of medium lay. 

Kope is laiowii as right lay or left lay. In left-lay rope all 
turns are reversed from those of the ordinary right-lay rope, 
the yam being s})un to the left. 

Twisting of hoisting rope may be lessened by soaking rope 
in water, then allowing it to diy out thoroughly. 

A common factor for hoisting load is 5 to 1 or one-fifth of the 
breaking strain. 

Small sheaves waste power and increase wear on ropes. 

Rope is weakened in a sliarp nip of any kind, whether due to 
a sphee, a bad lead, a hitch or a bend around a pin or a post, 
due to tensi(m upon the layers of fibre from the inside to outside 
bend, the outer layers being subjected to tension, while the 
inner layers are compressed. As a result, the outer layers wear, 
followed by othei*s in succession toward the inside. 



■ ROUND BAR RADIAL DAVITS 435 

Waterbury fibre-cUd wire rope ia bein^ extensively used by 
the United States Bhipbuiidera, It is a wire rope, each atrand 
of which ia served with the best grade of tarred Russian hemp 
marline. Tliis fibre covering prevents the chafing and wear 
of the wire strands during flexing movements, and after being 
in service a short time this fibre covering packa into the inter- 
stices of the strands, resulting in a rope having a smooth cyhndrical 
surface. It is unaffected with the changes in atmospheric 
conditions, and is therefore well adapted for the purpose of davit 
falls. Fibre-clad is about one-third the diameter of m&nila rope 
of the same strength. (See Table XXXI. on p. 432.) 

Galvanised rope should never be used for running rope, as 
the zinc quickly wears off and rust sets in with great rapidity, 
A good preservative is a mixture of crude petroleum and graphite. 

Wear increases with the speed ; it is, therefore, very essential 
that single wire falls should receive constant attention. 

Sheaves should be scored to the diameter of rope and particular 
care taken to see that there is no chafing the sides of the grooves. 

PRACTICAL RULES FOR ROPES, BLOCKS AND TACKLE.'* 

1. To find the safe working load of a luanila rope of given 
aiee, square the circumference in inche-s and divide by 7 for the 
load in tons. 

2. To find the size of a rope for a given working load, multiply 
the load in tons by 7 and take the square root of the product for 
the circumference of the rope in inches. 

3. To find the size of a rope when rove as a tackle to lift a 
given weight, add to the weight one-tenth of its value for every 
sheave to be used in hoistmg. This gives the total resistance 
including friction : divide this by the number of parts at the 
movable block for the maximum tension on the fall. Reeve "the 
fall of a sjze to stand this tension as a safe working load. 

EmmfU. — To lift 10 tons with a three-fold purchase, the fall 
of which, coming from the upper block, is taken through an 
extra sheave on deck for a fair lead. Required : the size of the 
fall. 

Total resistance, including friction, equals 

I 10 + 7 X jiJ=fiaHV 

Maximum tension on falls equals '^ "^^^^^^^ 
Size of fall, not« 2. equals V? X 2'^^^^^^H|^^_^ 
: 



436 SHIPS' BOATS 

• 

4. To find the weight which a given purchase will lift with 
safety, find the safe working load for the rope to be used. Note 
1, multiply this by the number of parts at the movable block. 
This gives the total resistance including friction. Multiply the 
total resistance by 10 and divide by 10 plus the number of 
sheaves used. The result is the weight that may be lifted. 

Eaumple, — ^To find the weight which may be lifted by a fall 
of 4J-in. manila rope as a three-fold purchase, the fall of which 
leads from thef upper block through an extra leader on deck : — 

4*52 
Safe working load — - = 2*9 tons 

Total resistance, bicluding friction, 6 X 2*9 = 17'4 tons 

17*4 X 10 174 
Weight to be Ufted ^r^^r, ^ lY ~ ^^'^ tons. 



The decisions arrived at by the International Convention 
for Safety of life at Sea, liave now been practically embodied in 
all the regulations issued by the Board of Trade. 

The standard weight for each adult person is estimated 
at 1G5 lbs., and the strength of davits, boats, and all associated 
equipment is based on this standard in Great Britain. • 

The davits fitted to foreign-going passenger vessels must be 
of suflicient strength to safely lower the boats into the water, 
fully equipped, and to carry the maximum number of persons 
for which they are allowed. 

The differeuce between 140 lbs. the old standard of weight 
per person, and 165 lbs. the present standard, makes a considerable 
difference in the ultimate test load to be placed on a large Ufeboat. 

To provide a basis upon which to construct a formula for 
obtaining the size of a radial davit of circular section, without 
the necessity of resorting to intricate calculation, a lifeboat of 
Class Ia, 28 ft. in length, complete with equipment, blocks, falls, 
and carr}'ing 50 persons, is taken as imposing a load of 100 cwts. 
on the davits, or 2 cwts. per person for which the boat measures. 
This is briefly stated as follows : — 

W 

where W — Total load on davits in cwts. 

X ~ Maximum number of persons for which the boat 

measures. 
w = Load on davits in cwt-s. per pei-son carried. 



ROUND BAR RADIAL DAVITS 437 

Take a lifeboat of Class Ia with the following standard of 
dimensions : 28*0' X 8*5' X 3*5', which gives an actual total 
capacity of 833 cub. ft., with accommodation for 50 persons. 

Then |§^ =3 -12 cwt. per cub. ft. of capacity 

or \^^l^- =3 2 CWts. per person. 

From Table XXVII. the weight of this particular size of boat 
is given as 119 cwts. (say 120 cwts.). 

Then Jjf 1^ = 14 cwt. per cub. ft. of capacity 

or ^^ = 2*4 cwts. per person. 

The formula which enables the shipbuilder to readily ascertain 
the correct diameter of davits of soUd round section, and approved 
by the Board of Trade, is as follows :— 



rf=^ 



L X B X D(H + 4S) 
C~ 



where L = Length of boat, in feet. 
B — Breadth of boat, in feet. 
D = Depth of boat, in feet. 
H — Height of davit, in feet, above upper support. (From 

upper surface of collar to centre of crosshead.) 
8 ^ Span of davit, in feet. (From centre of davit to centre 

of crosshead.) 
C =1 Constant, to be taken as 86 for iron davits, 104 for 

soUd ingot steel davits of from 27 to 32 tons tensile 

strength, and for hollow welded davits of from 26 

to 30 tons tensile strength. 
d = Diameter, in inches, of solid davit. 

The dimensions L X B X D are those which are ordinarily 
used in obtaining the correct capacity of a boat for appropriating 
the number of persons, as described in Section C of Part II., 
and illustrated in Fig. 23. 

The foregoing rule is only applicable when the weight per 
* person does not exceed 2 cwts. 

Boats vary in weight, and the details given in Table XXVII. 
will be of assistance in estimating the total dead load on the davit. 

A modification to the constant C will therefore become 
necessary in the majority of cases, in view of the increased 
standard weight of one person from 140 to 165 lbs., and the 
increase in weight in the majority of boats due to maintaining a 
minimum scheme of scantUngs. 



438 SHIPS' BOATS 

The difference in weight of steel and wooden boats is now 
practically negligible. 

For the purpose of illustration, let us take four separate cases, 
and apply the formula approved by the Board of Trade for 
securing the correct diameter of the davit. 

(a) Assume that the davits shown in Fig. 239, are of wrought 
iron and fitted on a passenger steamer where the full load has to 
be lowered into the water. 

Formula is — 



d = ^'LxBxD(H + 4S)^^ 



C 

. L == 240', B = 7-5', D = 30', H =. 100', S =^ 575'. 

The constant C is 86 for iron davits when the weight.per person 
does not exceed 2 cwts. If reference is made to Table XXVII., 
we find that the total weight of the boat, equipment, number of 
persons, blocks, etc., is 77*6 cwts. (say 78 cwts.), and the number 
of persons allocated is 32. Then the weight per person is 5§ =2'44 
cwts. The constant C (86) will therefore need modification, 
and the correction is made thus : — 

86 X 2 
2-44 ^ 

The formula will now be — 



^ ^ y24-0 X 7-5 30 (100 + 230) 
V 71' ' 



^ ^ 7^40 X 33 
V 71 



d^sy 



17820 
71 

d = \/250 

d = 6-3 in. =^ (j}.^" 

d = say 6 {\. in. 

The relative streiijujth along the tapered parts of the davit 
must be fully maintained. 

(6) For the second case, let us take the same particulars for 
the dimensions of boat, etc., as were used in example (a), the only 
difference bein*^^ that the davits are to be fitted on a cargo vessel. 
It has been j^^enerally considered that such a davit need only be 
strong enough to carry the boat, equipment, and a sufficient 



ROUND BAR RADIAL DAVITS 



439 



number of men to safely handle the boat during the ^process of 
lowering. No objection is raised if the diameter of thje davit is 
not less than that found by the Board of Trade formula^ but 
using 144 for the constant C. The davits are of untei^ted 
material. The procedure would then be as follows :-^ " ' 



d 



V 



L X B X D(H -MS) 
14A 



d = -Ai-O X 7-5 X 3-0(10;0 + 23- 
'^ ' ' "144 ~ 



0) 



d = 



,/17826 



144 



d = \/l23-7.: 
d = 5 in. 



5 



(c) Take another case, illustrated in Fig. 240, where the davits 
are made from ingot steel, the material having been tested and 
foimd to be within the limits of 27 to 32 tons tensile strength. 
The davits are to be fitted to a foreign-^roiw// passenger vessel, 
where the full load is to be lowered into the water. 

The dimensions of the hfeboat (Class Ia) are 28-0' X 8-5' X 35 
with an actual capacity of 833 cub. ft., giving seating accommo- 
dation for 50 persons. 

If reference is made to Table XXVII., the total dead load 
coming on the davits is 119 cwts. (say 120 cwts). Then the 
weight per person is ^-^J' =a 2*4 cwts. 

The constant C for steel davits is 104 where the weight per 
person does not exceed 2 cwts. 

In this case the constant will therefore need modification : — 



104 X 2 
2-4 



. 2-4 



Taking the dimensions from Fig. 240, the fornmla will thus 
read : — 

J _ .i/28-0 X 8-5 x"3-5(l"2-0 + 28-6) 
a _ ^ g^ 

d = . »/833 X^ 
^ 87 



d = 7-26 = 7i in. 



440 SfflPS' BOATS 

{d) Id the case of an open lifeboat of Class I., the entire cubic 
capacity is measured for the purpose of allocating the number of 
persons, but in a motor bocU the allocation of passengers or occu- 
pants is somewhat differently treated. The space occupied by 
the machinery, fuel tanks, etc., must be deducted from the cubic 
capacity when arriving at the proper seating accommodation for 
the number of persons. It is therefore necessaiy to take this 
feature into consideration when using the formula, which is based 
on the assumption that the weight of the boat, equipment, 
number of persons /or which it measures, blocks and falls, does not 
exceed 2 cwts. per person. 

In order that the formula may be used without any modifi- 
cation being made to the constant C, a simple method of dealing 
with a motor boat, or any other boat, when the actual weight is 
known, is to find an equivalent L X B X D at 2 cwts. per 
person, by dividing the total weight of the boat, number of 
persons, etc., in cwt., by 12 (12 cwts. per cub. ft. of capacity). 

As an example, suppose a motor boat fully loaded weighed 
78 cwts., and we wish^ to obtain the correct size of the iron 
davits to be installed on the vessel. 

78 
The equivalent L X B X D would be - = 656. 
^ •12 

Taking the same particulars from Kg. 239, as used in case 
(a), the formula will therefore be — 



d=^^' 



050 X 33 

86 



d = ^^"^ 
^ 86 

d = x/249 

rf=r 6-3or6,';;in. 

which ^dves the same result as the example worked out at (n). 

It therefore follows, if we have the weight of the boat, number 
of persons, equipment, blocks, et<'., or in other words, the total 
load comin»4 on the davits, that we can always find an equivalent 
L X B y D, by dividing this total weight by '12, which allows 
the use (jf the approved formula without any modification being 
made to the constant (.'. 

In dealini; with holloir davits, it is necessary in the fiurst place 
to asceitain the size of a solid davit by the usual formula and then 



ROUND BAR RADIAL DAVITS 



441 



proceed to obtain tiie equivalent section from the foUoAring 
formula, viz. : — 



or 



where 



d3 



". = V(^ X s^ i) 



d =j Diameter, in inches, of soUd davit. 

Dji =j Outside diameter, in inches, of hollow davit. 

df^ =3 Inside diameter, in inches, of hollow davit. 



m = the ratio 



Da 

d. 



Table XXXII. gives some equivalent sizes for hollow and sohd 
iron davits, approved by Lloyd's Register of Shipping.. 



TABLE XXXII 

Equivalent Sizes for Hollow and Solid Iron Davits. 



Diumoter at 


DLuiietcr and thickness 


Diameter at i 


Diameter and thi(*kne8a 


(lock, of solid 


of approved weldless 


deck of Holid j 


of approved weldless 
drawm steel 


wrouKht-lron 


drawn steel 


wTOURht-lron 


davits. 


iiollow boat davits. 


davits. 


hollow boat davits* 


luclics. 


Inches. 


Inches. 
6 


Inches. 


3 


4 XA 


7} X J, 


3 


4ix A 


6i 


Six A 


H 


4ix A 


6i 


8i X A 


^ 


Six A 


n 


9 XA 


4 


51 X ,»„ 


7 


9 xA 


•*i 


»i X A 


7i 


9JxA 


4i 


6 xA 


7A 


9ix^, 


4i 


(!i X r". 


7i 


101 X J-, 


6 


H X A 


8 


10i.x A 


51 


' X A 


«i 


lOi X A 


5i 


nxA 


8i 


11 x,». 


5.J 


'Jx.-V 




1 

1 



The formula approved by Lloyd's Register is the same as the 
one adopted by the Board of Trade, with the exception that the 
constant C is slightly modified, which is as follows : — 

1. When the davit is to be of wrought iron, and of sufficient 
strength to carry the boat, its equipment, and a sufficient number 
of men to launch it, the value of C is to be 144. 

2. When the davit referred to in (1) is to be of wrought ingot 
steel of from 28 to 32 tons per sq. in. tensile strength, the value 
of C is to be 174. 



442 SHIPS' BOATS 

3. WTien the davit is to be of wrought iron and of sufficient 
strength to safely lower the boat fully equipped and carrying 
the maximum number of persons for which it is intended, the 
value of C is to be 82. 

4. WTien the da\it referred to in (3) is to be of wrought ingot 
steel of from 28 to 32 tons per sq. in. tensile strength, the value 
of C is to be 99. 

Note : — Items 1 and 2 have reference to cargo vessels, and 
3 and 4 to passenger vessels. 

The following particulars have been selected from the 
regulations recently issued by the Board of Trade in Greneral 
Circular 1606 : — 



BOAT-LOWERING APPLIANCES 

The following requirements apply to all new ships whether 
passenger or cargo, and should also be compUed with as far as 
practicable in the case of existing ships. 

Blocks. — The upper and lower fall blocks should be of ample 
strength for the load to be carried, and the width between the 
cheeks of the blocks should be half an inch greater than the 
diameter of the rope for new ropes 4 in. in circumference : 
for smaller ropes the clearance should be in proportion. Lower 
fall blocks should be fitted with a suitable loose ring or long link 
for attaching to the sling hooks unless some approved form of 
disengaging *:ear is adopted. 

Rope. — The rope used for falls should be of nianila or other 
suitable fibre and should be soft spun with at least 33 yams in 
each strand of a 3J-in. rope. The breaking load for 3^-in. 
rope should not be less than 5| tons, and each yam should be 
capable (^f carrvin<^' on an average not less than 185 pounds. 
Owners should be advised to require dealers from whom they 
obtain rope to guarantee that the rope comphes with the above 
standard. 

Bollards. — Suitable bollards for lowering boats should be 
provided in all cases. It is recommended that in new ships and 
where practicable iii existing ships a double bollard should be 
fixed to each davit. This allows the man tending the falls to 
keep tlie boat well in view while it Ls being lowered. The bollards 
should be attached to tlie davits in a position where they will not 
foul the boats when being s\vung outboard. If, however, the 
lowering b(;llards are fixed to the deck, suitable fairleads must be 
fitted and so arranged that the boat is not lifted in swinging out. 




ROUND BAR RADIAL DAVITS 



If bollarda are not fitted other equally effective appliances should 
be provided. 



i 



APPLIANCES FOR PREVENTING FALLS FROM CABLING 

Experimeats have been made with a view to ascertaining 
what appliances can suitably be adopted for preventing falls 
from cabling or twisting together after the first boat is water- 
borne and the lower blocks have been unhooked. After oon- 
siderinfi the results of these experinieuts, the Board of Trade are 
of opinion that a suitable span between the lower blocks should 
effectually prevent such cabling. 

The span should be of wire rope fitted through a short length 
of tube securely attached to the top of each lower block, so that 
the wire span slides horizontally and parallel to the pin of the 
sheaves. This tube makes the resistance act at an increased 
leverage while at the same time allowing the span to sKde through 
the tube tfi make up for any variation in the distance between the 
blocks. Suitable toggle or other stops should be provided to 
prevent the span slipping entirely out of the tubes. Any other 
equally effective^'plan of fitting wire spans may, however, be 
adopted. 

Alternatively, a suitable rigid span or spreader may bo 
provided. This will effectuaUy prevent cabling, but on account 
of the danger attending its use, special measures will be necessary 
to minimise the risk of injury to the occupants of the boat, to 
provide against the pfissibJlity of fracture of the span if the boat 
is not kept horizontal during lowering ; to prevent the span 
fouling the davits when the boat is being swung out and to 
enable it to be readily detached. \V'henever it is proposed to fit 
a rigid span or spreader of a type not previously approved, full 
particulars of the appliance must first be submitted for the 
Board's consideration and approval. 

On account of the difficulty of instantly unhooking very 
hea\'y non-toppling blocks by hand, and with a view to reducing 
the risk of injury to boat or occupants after unhooking, as well 
as to facilitate the recovery of the falls, everj- effort should be 
made to reduce the weight of these blocks and the span to what 
is necessary only for ensuring ample strength, durabibty, and 
ilficiency in preventing the falls fi'om fouling when being 
recovered, Where the weight of a ntm-toppling block plus half 
the weight of the span exceeds 100 lbs., it is strongly recommended 
that an approved disengaging gear be fitted in ^e boat. 



Hi SHIPS' BOATS 

SECTION C— PATENT APPLIANCES FOR LAUNCHING 

SfflPS' BOATS 

The Welin Patent Davits. — It seems almost saperflnous to 

describe in great detail the various apparatus whidi the Wdin 
Davit & Engineering; Co., Ltd., have evolved for the purpose of 
providing the most expeditious and satisfactory means for 
launching ships' boats, because they are so well known and under- 
stood by shipowners and shipbuilders throughout the continent 
of Europe and in America. There is no question appertaining to 
the life-saving equipment on ships which has not received this 
firm's careful and studied consideration. 

Attention has already been given in Section A to the various 
systems which are in operation for dealing with the transpor- 
tation and stowage of lifeboats, and patented by the Welin 
Davit Co. 

The principal types of Welin davits comprise single-acting, 
double-acting, and overframe. There are, of course, numerous 
modifications of these three j>rimarv types, and to which only 
brief reference can now be made. 

** S.A.'' The Sw(/le-ac(i fif/ Tt/jje is made in fifteen different 
sizes and is mainly intended for operating one lifeboat only. 
Figs. 2455 and 244shov; this particular da\at installed on one of the 
largest ocean-gointr passenger stoamera, and incidentally depict 
the crew at Ijoat drill. The frame and davit arms are made of 
the best cast sterol of a tensile strength not less than 60.000 and not 
more than 72,000 pounds per sq. in., with an elongation of 22 per 
cent, in two incln'S. The quadrant is geared to a path on the lower 
portion of the frame, and the travelHuL^ screw is made of "Tobin " 
or phosphor bronze, abutting on hardened steel thrust washers 
so as to reduce friction to a minimum. The design of the 
quadrant gives increased leverage and power when the stresses 
on the davit are at tlieir maximum. In operating the screw the 
lifel)oat is lifted from the stowage cliocks \\ithout any previous 
adjustment and allows the keel and bilge of the boat to easily 
clear the deck of the vessf^l. The working of the mechanism 
to bring the boat from the stowing to the outboard position is 
simplicity itself, and would enable even an imskilled operator 
to handle the same with saf«'ty should the necessity arise. 

"\P " Ti/]/r. — This is a simple modificaticm of the single-acting 
type, obtained by somewhat shortening the frame, and intro- 
ducing a ioniser arm. It is used in cases where an open Clas? I. 



PATENT DAVITS, ETC, 445 



m 


m 


F' i 

H.I 

i 




^ 


g 




k 


^^^ 


ll 




446 SHIPS' BOATS 

lifeboat is carried above a Class II. boat having collapsible bul 
warks, or where one open Class I. boat is carried above another; i 
the latter case a special form of pedestal chock is used, otherwis( 
the workhig of the gear is exactly the same as in the othe 
types. Fig. 129 shows this particular type of davit fitted unde 
the conditions described. The lower boat being a 28-ft. Lundu 
decked lifeboat. 

Trifling modifications are introduced into all the various type 
when wire fulls are used, but in no case do such modificatioufi 
where they exist, in any way alter the general w^orking principl 
of the gear. 

" D.A.'' DouhU'-acting Type. — This design of davit is illustrates 
in Fig. 245. Tlie purpose of this davit is to handle a doubl 
row of boats as the photograph indicates ; it will be noticed tha 
the ([uadrant at the heel of the arm is considerably extende( 
beyond that of the single-acting davit. 

'' F '' Tf/ipe- (Single and double-acting.) This particula 
davit is utilised when a number of boat^ have to be transferre< 
across tin* deck to a point within reach of the lowering davitji 
and can b(» used in conjunction with either the single or double 
actiui,' davit. 

" L " Tt/pf' is a particularly stnmg davit used for handlin« 
steam and iiiot(u- laimch(\s, hospital boats, ete. 

** " Tj/jtc is an overframe davit, the shape of which is in ths 
form of a ^^oose-neck. The illustration given in Fig. 246 indicates 
the practical features of this desiiiu. The keel of the boat restf 
on a |)roj(Htion attached to the davit arms, and the boat neatly 
stows ill chocks also secured to the arms. There are three 
posit i(jns in wliicli the ])oat c^an be carried, viz., inboard, harboiu 
position, and outboard, the chocks being so arranged as topreveni 
any ])ossible movement, of tlit* boat at each of these positions. 

This type of davit is well suited to accommodate the emer- 
<^^ency boats, and ([iiite a lari:e number were fitted to Royal Fleet 
auxiliaries durin^r the Gieat War, for the British Admiraltv. 

A distinct advantaue is secured when this davit is fitted to a 
promenade deck, as an imobstiiicted view is obtained under the 
keel of tlie boats by the passen;iers. 

** M '' Ti/jKi. — Tlii< is a small single davit fitted to yachts for 
accommodating the dinghy. 

"* L.I), " Jf';//7>(^■— Space will not permit the use of many of the 
photoiiiaphs which aic still in the ])ossession of the writer, illus- 
tratiiiLT the various dt^vices of the *' W'elin '' systems of dealinir 
with the launchinii of ships' boats. This type is used on lar^^e 



us 



SHIPS' BOATS 



%'««s4lij. w)j«r<; it ha« l>«<eu found undesirable to plac« the whole 
of tilt lifetx/abi "ti th^^ upper d^-k. The aTrangement gives a 
cltmr iiriitiiiituuli: d«-k and the boat^ bein^' »tuat«d nearer to the 
wati;r timti if nt'i wi-d on the b<jat deck, increaficd stAbilit;' is gives 
Ui tbcr v«i>»^l. 

The Norton Sheath Screw Davits. — This partioalar daWt was 
di-nitai'^f by ilr. Xort'^n of the liiited States of America and is 




u^^^ iLi.iiiulii.'iumi hv ili.^ .\iii.-iiiiin Halsii {.■<.iiii>uiiv. Inc. (Welin 
MarJ-ir K.,>ii|mK'iil Cu.l. I.nim Island City. Now York. 

'I'lif ili'.-i;;n is \ I'l y siihj'li' add t 111- cunibinatiim ii?Hliiiost entirelv 
huill ii|. iii.iii stnuiinai .M.-.-l ;uid is llicrofor,- ("mparativeh- 
lij'hl. 'I'lii' ila\il arm is an II \>nv liaviiii; ii loi«cd liead seciirelv 
iiv,-i,->l [h.-i.-i,., will, ^,M«1 solid liiii,i;<-s at ihehwi. The fraink, 
III ili> k >taiLil, i:s iun.--inni.\l I't [■mikt.'t plute^ and augle bais. 




PATENT DAVITS. ETC, 



The pivoted arms are actuated by a stee! screw connected to the 
deck stand, and operated by turain}{ a crank. 

The actuating screw and all ita associated parts which are liable 
to be affected by the weather or damage, are well protected by 
a sleeve or coverinfj tube. Arrangements are made to keep the 
screw and sleeve well coated with grease. 

An iUustration of the gear is shown in Fig. '247. 

Large numbers of vessels constructed for the United States 
Shipping Board Emergency Fleet Corporati<in are fitted witli tliis 
particular davit. 

The Babeock and Wiloox Patent Davits,— The limited scope of 
this particular section of the subject will not allow an 
extensive detailed description which many of the important 
launching devices deserve, but sufficient reference will be made to 
the various characteristics of the designs t^ enable the reader to 
form a general idea of the operation of each davit. 

Messrs. Babeock and Wilcox have produced davits of a design 
baaed on theoretical principles which are sound and effective. 
They are made in three general tj-pes, all of which are operated 
by a positive acting gear which enables the boat to be traversed 
safely even when the ahip is rolling. 

One of the many advantages of the design is that the davits 
are so constructed to Uft the boats from their inboard stowing 
position without subsidiary transporting gear, and transfer them 
to the launching position at the ship's side. 

Another feature worthy of recognition, is that the boats 
are carried in a level path, consequently a minimum of power is 
required for the actual operation of latmching. 

The three important types of davits are briefly described as 
follows : — 

Singh-aeti-ng Type. — This davit is designed to deal with a 
single boat or a single bank of boats, either of tKe nested or the 
super-imposed type, stowed at the ship's side. 

The photograph in Fig. "248 shows a specimen of this particular 
davit. The combination consists of a jib, to the head of which is 
attached a special form of lever. At the extreme end of the lever 
is situated the pulley over which the wire falls are led to tlie lower 
blocks. The lever is also attached to a guide bar which is secured 
to the davit foundatitjn frame. 

The traversing gear consists of a worm mounted on the handle ■ 
^^ shaft and engaging a worm wheel fixed to a steel crank, which 
^L is connected to the jib by a rigid steel bar. 
^H When the shaft is Ritated, the jib moves outboard, and at the 



^ 


(60 


SHITS' BOATS ^M 




/*^^ 


^"K^ 


Btl L 


^^^t 






irT"Fi*>J - 1 


^" — -^ 




^1 


fcttSr??*^"' 




Fig 24S.— 


Snljcnc-k and » ilcox iiulciit sin^k-LOtii.c .1 imH 




: 


l|^\ 1 






' u 1 \ \. ■' ■ 




1 


^^H^^^^H T "."jH^Sfl 




JH 


^HjjjH 




'iG. ai9.— Tlie MurtJn patent darits. .^J 


^K^ ^^k 


L -^^^^H 



PATENT DAVITS. ETC. ACA 

I same time the lever moves in unison with the jib ; the n»Iler 
T at the head oi the jib consequently travels outboard in a horizontal 
I plane, the effect of which enables the boat to be traversed borizon- 
[ tally, its weipht ia therefore not actually lifted, and the power 
I to operate the davit is reduced to a minimum. 

This gear enables a heavy boat to be moved outboard against 
a heavy list of the vessel. 

The davits can be made of sufficient length, and provided with 
L smple clearance, t^i enable a tier of lifeboats to be stowed imder 
I them. 

Doubk-nclir^g Tyjie. — ^This davit is designed to deal with 
multiple banks of boats stowed close to the ship's side. It is 
constructed on the same principle as the single-acting; typ<i, but 
tlie jib and lever, in this case, are adapted to swinj; to either 
side of their vertical positions. 

The position of the jibs are arranged to permit of the boat 
passing between them, and the lever or derrick arms are fitted tii 
■ swing past the jibs. By an arrangement of curved rests at the 
head of the davit, the guy ropes adequately support the jib when 
inclined to port or starboard. 

Special traversing-gear has to be fitted with the double-acting 
davit, which consists of two steel ropes attached to the fiilcnim 
pin of the lever. These ropes spread out to either side and pass 
over sheaves on the foundation frame, to an operating barrel, 
on which they are wound in opposite directions. 

Wlien the barrel is made to rotate by the worm gearinj* 
attached to a shaft and handle, one of the ropes is paid out and 
the otlier is drawn in, so that the jib is swung in the corresponding 
direction. Consequently the guy ropes cause the levers to awing 
out in proper relation, and the boat is carried in a parallel path to 
tJie deck ; a principle wliich is maintained in all the davits con- 
structed by Messrs, Babcock & W'ilcns. 

Long-reach Davits. — A photfjgraph of this type is shown in 
Fig. 153, which also serves to illustrate the description given of 
the double-acting davit. The davit is being operated to transfer 
one of Clemson and Murray's nested boats from its stowing 
position to the ship's side, having sufficient reach to lift it clear 
of the " nest " and safely transport it clear of the remaining 
boaUi which are stowed in their chocks. 

BoatA can thus be stowed aide by side in ordinary chocks 
81*1088 the deck, without subnidiary transporting gear, and the 
davits have sufficient leaih to launch the boats on either side of 
the veflsel. The number and position of the boats govern the 



452 SHIPS' BOATS 

# 

necessity for fitting one pair of double-actiDg type of davits at 
the centre of the vessel's deck, or one pair at each aide. 

Messrs. Babcock and Wilcox have gone very carefully imd 
extensively into the question of the most suitable operating 
mechanism for lifting the lifeboats and safely controlling them 
during the operation of lowering. The firm has designed a 
special self -trimming gear to prevent one end of the boat being 
lowered faster than the other, and attached to the lower fall 
blocks is a light chain span which ensures that the blocks will 
neither topple nor spin during the period of re-hoisting. 

Provision is made for operating the davits by suitable hand 
winches, fitted with a double barrel for controUing the lowering 
of the boat, and a special warping drum for hoisting. 

The large davits can be fitted with independent motors driving 
hoisting and traversing winches. 

A magnetic brake is fitted on the boat side of the chancre 
speed gear, capable of sustaining and lowering a fully loaded 
boat, which brake is also supplied with a hand release. A speed- 
limiting brake is fitted so as to prevent the boat being lowered too 
quickly. 

Independent mechanism is provided by crank handles of 
sufficient length to acconmiodate twenty men, so that in the 
event of the electric power supply breaking down, the work of 
launching the boats is not interfered with. 

Messrs. Babcock and Wilcox's davits have been fitted to many 
large and fast passenger steamers, including the recently con- 
structed Melita and Miniedosa, owned by the Ocean Service of 
the Canadian Pacific Railway Company. 

The Martin Patent Davits. — The construction of these davits 
is unique and differs from any other type of gear at present 
fitted on vessels. They aie a })ractical adaptation of the crane 
and wincli principle applied to the handling and launching of 
a loaded lifeboat. 

The whole of the working parts are enclosed in a watertight 
con)])artment, which prevents snow and ice interfering with the 
efficiency of the davit. This })rovisi(m is a matter of considerable 
importance when vessels cross the North Atlantic during winter 
months. 

The davit arms are built up from steel plates and angles, thus 
ensuring the maxinmm amount of strength with a minimum 
weight. 

If reference is made to Figs. 250 and 251 which illustrate in 
outUne the general arrangement of the Martin Patent Davity it 



454 SHIPS' BOATS 

will be Been that the davit arms travel on caniTshaped tracks 
situated at each end of the lifeboat, and are moved outboard or 
inboard in unison by the turning of a crank, which operates a 
worm gear attached to a shaft connecting both arms of the 
davit. On each end of this shaft is a roller to which are fitted 
steel pins. On • revolving the shaft the steel pins engage with 
holes in the track, and the davit arms thus triavel securely and 
steadily into the extreme outboard position. Both arms are 
engaged to the one fore-and-aft shaft so that they travel out- 
board in complete alignment, which is an important feature of 
the design to be commended. 

The recommendation of the Departmental Committee on Boats 
and Davits has been embodied in the lowering gear by the adoption 
of two-part wire falls instead of the usual six -part manila tackle, 
and simple means are provided for adjusting these so that the 
boat will descend- on an even keel in case of a vessel sinking by 
the head or stem. 

The two-part wire ropes enable the davits to quickly recover 
themselves to the inboard position for the launching of additional 
boats, where the latter are stowed in tiers or abreast of the 
original boat, and prevent the difficulty which is often associated 
with the manipulation of ordinary manila rope falls in becoming 
** cable-laid," or the blocks ** toppling." 

Independent lowering at each end of the lifeboat is sometimes 
responsible for placing the occupants in considerable danger and 
tlie designers of the Martin davit have endeavoured to obviate 
such a condition occurring with their system of control. 

The wire falls aie wound on a drum situated in the watertight 
casing at the lieel of oin) of the davit arms, and are controlled by a 
brake from a liaiid wheel which is situated in a convenient position 
close to the shi])'s side, to enable the operator to witness the whole 
I)rocess of lowering, control the speed, and choose the best oppor- 
tunity for the boat to take the water. 

The purpose of the drum is t-o permit the falls to nin out 
smoothly and obviate the nc^cessity of coiling u]) great lengths 
of rope on the boat deck, which interfere with the operation of 
launching other boats. 

To bring the boat up again from the water, a lead is taken from 
the nearest winch or electric motor to the drum on which the wire 
falls are wound, and the boat is brought inboard by passing the 
lead over the shaft wliich runs the boat out or in. 

If electricity or steam is not available, the operati(m of hoisting 
and stowing the boat can be undertaken by manual power. 



» 



PATENT DAVITS. JiTC. 455 

To relieve the weight of the boat oil the atowing chocks 
immediately before loweruig, a ratchet device is fitted and can be 
operated by one man. AU bearings are self -lubricating. 

A photograph of the apparatus fitted to the Brocklebank 
liner Maidan is shown iu Fig. '2i9. 

The writer has inspected the gear on board this vessel, and 
the whole process of launching the lifeboat into the water was 
successfully accompUshed by only two members of the crow 
operating the gearing. 

It naturally followti with all tncchanically-operatod launching 
de.vices, that the gear needs t'> be periodically overhauled by the 
ship's engineers, and the working paits maintained in proper 
order. 

The constant use of the davite during boat drill should 
accustom and train the crew for the successful operation of 
launching the lifeboats. 

The Martin "Simplex" Davit is the Martin Patent Davit 
without its mechanical lowering apparatus. 

The construction of the davit arms are built up from steel 
angles and plates, in a Hinular way to the patent davit and are 
run outboard and inboard in unison by the turning of the worm 
, gear operating the fore-and-aft abaft. 

Instead of the single wire ropes and brake gear, ordinary 
inanila falls are supplied if the shipowner wishes them to be so 
fitted. 

The " Simplex " davit can be converted into the " Martin " 
davit by substituting a new arm with the winch lowering-gear. 

The Martin davito are manufactured in Great Britain by the 
well-known firm of Messrs. Sir W. G. Armstrong- Whit worth & 
Co., of Newcftstle-cm-Tjiie, and further particulars of the gear 
can be obtained from Messrs, Ogilvy, Gillanders & Co., of Liverpool 
and London. 

Graham's Patent Single Davit— The one-davit centre slinging 
of lifeboats is extensively in use on ships of the American 
and French Navies, and to some extent in the British Navy, 
For several years there has been in use on boai'd a number of 
steamers of the Ellerman City Line, and giving every satisfaction 
to the owners, Graham's Patent Single Davit, with central 
suspension. A photograph of the apparatus is shown in Fig. 252. 

This davit arrangement is the invention of Captain John 
Graham, who has had long and intimate experience, as an officer 

I and master mariner, of the many difficulties associated w'**" *''e 



15G SHIPS' BOATS 

The raisftH d'etre of tlie Graham Patent Single Davit inainli 
consists in the attempt to provide a safer and more expeditiou 
method of lifting and lowering lifeboats than is afiorded by th 
ordinary two-davit and manila falls system so long in use. 

With the Graham single type of davit, the lifeboats ai 
susjxMided centrally by a single chain fall, ensuring that they ar 
raiseii and lowereil on an even keel under the control of one man 
The form of disengaging gear used, automatically unships tL 
sling as soon as thr boat is waterborne. 

Thv sling arrangement consists of two rigid rods, spreai 
diagonally to take one-third of the mid-length of boat, an 
securely bolteil through keel and keelson ; each rod having at it 
upp(»r end a short length of wire rope attached to the ring whie 
coiUKM'ts with the disengaging hook. The latter has its point s 
weiglit<Hl and hinged, that wh(»never the boat becomes waterbom 
and the. t<'nsi()n of the load is removed, the point falls automatical]} 
and instantly unships the ring and sling. The short flexible tO] 
portions (»f tlie sling liang from the rods which are allowed t 
remain upright, until the Ixiat is clear of the ship's side. By th 
simple withdrawal of a j)in at the thwarts the rods can be readil; 
hinged down t^> lie flat along t he thwarts. The rods, while on dut;} 
are held in position (to prevent the boat oscillating athwartshi] 
when being loaded and lowered) by means of eye-plates fixed t 
the thwartsS. 

TIm' ( Jralujm single (hivit is a steel ** built " davit of the derric 
(U'drr, ol n'(titn;^ular section, and is a combined manual and nic 
chanical power apparatus ; whilf it is als(» well adapt<xl to bein 
operated by elect He powiM" entirely. It has mcjuntedupon it, at 
convenient ln'iiiht. enclosed in a stet'l casing, operating gear in th 
form of a single hand winch, fitte<l to which is a self-sustainin 
screw l>rak<'. Tliis nu'clianical .i;earing is abh^ to swing the boa 
out against a list, and the single man controlling the winch ant 
brake, can hold tlie. boat at any pcmit, either in lowering o 
hoistin;:. 

The fall is mach' of special H.li. tested chain, in the form of j 
gun-tackle purchase which, for th<». purp(»se. is claimed to h 
preferable to either wire or manila rope. It is led down over giiidt 
])ulh'ys from the interi(u*of the davit, and. working over a spi-ockei 
wlieel it stows itself in the hollow bottom j)art of the davit betweei 
th(* two decks which thus selves as a chain locker. C onfusion u 
thus obviated on deck around the boat static ju in the absence 
of a large (puintity of trickle. 

The wcidit of the Graham davit for a 28-ft lifeboat, wit! 



PATENT DAVITS, ETC. 



457 



all j;ear complete, ia 30 cwta., which ia a saviuj^' in cimipariMon 
with two ordSnsry davit<i and f^ear. 

\Vhile mechanical means for handling; lifeboats of tho stuiidatil 
size seema a modem necessity, it is not to be ovurlnokud that an 
ideal arrangement is one which is effective by mechanical means 
or by manual power alone. The Graham davit ia not only 
devised to accomphsh the work mechanically aided, but to operate 
by motor power entirely, if desired. 

Messrs. .famea Howden & Co., Ltd., of Glasgow, who are the 
proprietors of the patent and makers of the Graham davit, are 




I 



now fitting_these davita with electric motor power in combination 
with the present hand f'car. 

There are many devices connected with this typo of davit 
to recommend its adoption, and in addition to the City Lino, 
other shipowners have installed it on their vcseole, includlnj^ 
Messrs. Lamport & Holt. Meaars. C, T. Bowering & Co., the 
Burmah Oil Company, Royal Mail 8. P. Coy., ct«. 

The Steward Patent Davits.^ — An illustration of one of tiiese 
davita is given in Fig. 253. This particular design ia arraiigud 
to launch an ordinaiy open boat of CloB* ' d above a 

Lundin " boat of Class II. 

These davits have been liosii: m1 by 




458 



8UIP«' BOATS 



tliD StoWttRl Davit »U(1 fkjuipmeut Corporation of Now York 
City aad HudBOD, N.Y. 

The design ie uui<iuu aud simple, ba^ed on scientific 
principles. The system combiues stren^^tb with lightuoss s 
efficiency. 

At first glance, the apparatus very much rosombles the Wei 




davit, but a closer lusiwction will prove that the mechanisDi is 
entirely difiecent, although each patentee aims at securinj- the 
f-roatoat purchasing power from the operating gear when the 
stresses on the davit are at their niaximuui. 

The davit anns are made from good quality Htciel castiuga j 
f Section, which are shaped at their lower ends to fit over I 
davit frame. Connecting the davit arm to the frame is i 



i 




PATENT DAVITS, ETC. 

I lever at tha lieel ; the davit therefore pivotu about two dxcs. 
The operating gear cnnsists of a crank-haiiclle attached to a screw 
shaft, whicli engages a tnick cimnertoil t^i the atm of the davit. 
The truck travels with rollerB on the frame path and ite mechanism 
is designed to give.aupport and keep the davit arm in ahgmnent. 
Effective means are therefore adopted to move the boat out 
smoothly and rapidly to the outboard position. 

In the extreme inboard position the davit arms lie slightly 

^ outboard of the centre of gravity of the boat, so that on turning 
the crank-handle, the davits laft the boat from the atowinj; 
chocks, without any previous adjustment to the falls, and the 
keel consequently travels in a path well clear of the deck. 

• The patentees naturally have every confidence in the design 
and construction of this apparatus, to carry out all that is required 
from the various authorities controlling the life-saving equipment 
of merchant vessels, and from observations made by tho writer 
when cariyii^j out certain testa in the Hudson River at New York, 
the gear worked very satisfactorily and was able to withstand the 
severe stress of liftuig a loaded boat from the wat«r when the 

' davit arms were at the ejctreme outboard position ; a condition 
that would never be present in actual service. 

A large number of the Steward davits have been fitted to both 
cargo and passenger vessels constructed in the United States of 
America. 

The HeEaohnie Patent Boat Lowering Apparatus.— A very 
simple and effective device has hi-cu ili'sigiicd by Mr. A. 
McEachnie of Port (.■Wgow, ticotland, for dealiiifi with the 
question of hoisting and JowcririK ships' boats. The invention 

' has been recognised by the British authorities exercising control 
over the construction of standard shijis during the war. an<l 
several sets of this gear have already been fitted on cargo 
vessels. 

Extensive trials were carried out by the Board of Trade 
ofiicials before the apparatus was allowed to be installed on board 
passenger or cargo vessels, and having received the favourable 
consideration of this department, shipowners may therefore have 

' confidence in the reliability of the mechanism to speedily transfer 
lifeboate from their stowing position on the boat deck to the water. 
The apparatus is mairtly built up from stnictural steel, which 
combines strength with a minimum of weight. It consists ( ' 
a rectangular frame composed of channel bars worked bac' 
back in tho upright standards and well bracketed to a I 
horizoutul bar at the head. The bed of the frame is pivot 



460 SHIPS' BOATS 

t 

the deck to a stout hinge secured to two deep angle bars well 
attached to the boat deck with through bolts. . The lower ends 
of the frame are also provided with brackets whicli limit tiie 
extreme outreach and inboard stowing position of the apparatus, 
so that when the frame is in the outboard position, the bracket 
is resting on the deck plate, which reUeves the operating gear of 
any stresses which are transmitted to the frame during the process 
of lowering the boat. 

The photograph taken on board the S.S. Data when in 
Glasgow, is shown in. Fig. 255, and clearly indicates the various 
details referred to in this description. 

The frame is operated by a screw working in a tube or sheath. 
The tube is attached to the upper end of the vertical frame arms % 
and the screw is geared to a bevel wheel combination attached to 
a standard or deck bracket arrangement. The operating gear 
is worked by man power with the aid of crank handles, the thrust 
on the bevel wheels being t^ken by ball bearings. 

The upper blocks are well secured to the horizontal bar of the 
frame. Stout bollards are fitted to control the falls when lowering 

o 

the boat. / 

The first action of the operating gear is to lift the boat suffici- 
ently from the chocks to aljow the latter to be hinged down. The 
path traversed by the boat allows the keel to clear the ship^s side. 

Passengers can be embarked when the boat is inboard or at 
the deck cd^e, the apparatus being well controlled even when the 
shij) is rolling. 

It will be noticed from Fig. 25;") that protection plates are 
secured to the deck angles at the heel of the upright frame bars, 
to prevent a ])ers()n's foot from coming into contact with the 
brackets. Piotectivc measures are taken to obviate the diffi- 
c.iilty of ice or snow intorfeiing witli the brackets which Umit the 
extreme positions of the frame. 

Harland and Wolff's Patent Apparatus for Lowering and Raising 
Ships' Boats. — As will be seen from the illustration given 
in Fig. 251, the davits are of considerable length, and spaced 
far enough apart to allow the lifeboats to pass between them. 
Tliey are free to turn on horizontal pivots, and the operating gear 
is so arrangi^d that the davit arms can be turned in both directions 
through a large angle from tlic vertical. It is, therefore, possible 
to stow a number of open boats of Class J. side by side, in a row 
across the deck of tlie vessel, which can be launched from either 
side of the ship. 

Facilities are provided that enable the passengers to take their 



PATENT DAVITS, ETC. 461 

places in the boats before they are transferred to the ship's 
side. 

Single wire rope falls are used instead of the usual maiiila 
tackle. 

The apparatus can be worked either from the ship's electric 




generating plant, or alternatively fiinn the emerf-ency plant 

I which is now the usual installation in nii>st niotleru passini^nr 
StoamerM. 
Powerful motors are fitted tn ensure that the lai^est toadtd 
boats oan be transported with rapidity ; all the movements O^j 
the apparatxis are controlled by one man at each davit. ShouW | 
an accident happen ti} one of the men manipulating! tlie gearing, / 



462 SHIPS' BOATS 

limit switches are provided, which prevent further movement of 
the davits until another operator is installed. 

Powerful electric lamps are fitted at the top of each davit, 
which <^rcatly facilitate the operation of successfully launching 
the boats into the water on a dark night. 

The Harbinger Boat-lowering Crane. — ^Reference has been 
made from time to time 't>o various recommendations made 
by the Boats and Davits Departmental Committee, and attention 
may here be drawn to the reservation made by one member of 
that committee to the objections to ordinary davits and boat 
falls, wherein he says : " Improve^l means for Ufting and lowering 
" a full complement of boats (the majority being in protected 
*' positions) by means of electric cranes placed inboard and 
'* by a siii^k^ wire fall and bridle, the cranes being actuated by 
'* a Hp<HMal ^oneratint; plant with independent internal combuatian 
'' en;^ines, situattnl at the hi«^hest available point above the water- 
'* line (this plant would also be available for lighting and wireless 
" tehigraphy) are fu!ly ilhistrated in plans, etc., etc." 

An arrangement has been designed by Mr. Harbinger of Mark 
Laru^ Loutlon , to meet these various recommendations. The iilus- 
trati(m giv(Mi in Fig. 2r)(; gives an idea on a small scale of the 
general features of the design. 

Th(5 whole of the gearing is enclosed in a steel casing, secured 
to the (leek close to the ship's side, which gives the necessary 
j>r()to(^fi()n from the action of sea water, etc. 

Th<* vYiiwo conibination is formed by a vertical hollow standard 
or post, and a horizontal ami. t-o which is attached a special 
designed yok<' so rontrolh^d that it always remains parallel to 
the slii[)'s sidr and ])]nnil)s tlie ctMitre-line of the boat. 

Th<'. turning out of tlir boats is operated by a two-speed. gearing. 
TIhj g(»ar for hoisting coiisists of a right and left grooved drum 
on which coil two siniilc win^ falls. The drum is connect-ed to 
the licaring iui<l both arc })rotcctcd by the steel casing. 

The wire falls tra.vr»l from tlic drum up the hollow standard, 
|)assing throiiL^li the tubular horizontal arm out t'O the two ends 
of tlu^ yokt^ ami down to tln^ lifting hooks attached to the 
lil"«^bt>at. 

The actual o|)era.tion of launching, it. is considered, can be 
(•(•utrolhid by one man, who is in a position to wat-ch the boat 
until it. is waterborne. In case of accident to the operator, the 
boat beciuues staliouarv until the brake is releascMl. 

The position of the crane is arranged to operate a group of 
live bojits. A rapiil uejir is |)rovide(| for the return of the 




PATENT DAVITS, ETC. 463 



4 


p\. 


-^ 


if\fk 




-- 


^w- 


-Ky^^-^-^M^ 


I 




464 SfflPS' BOATS 

empty falls and a slow gear used for the lowering and laismg of 
boats. 

It is claimed that the total weight of this gear ia considerably 
less than that of ordinal}' davits required to launch the same 
number of boats. 

The length or outreach of the horizontal arm is such that the 
boats can be laimched when the vessel has an adverse list, and 
can be brought close to the ship's side to allow for tike 
embarkation of passengers. 

. This gear is quite a recent production, and owing to tike 
effect of the w^r delaying the construction of passenger vessels, 
little opportunity has been given for its installation to enable a 
fair expression of opinion to be stated as to its advantages under 
actual service conditions. 

Ross and Anderson's Patent Apparatus for Transpoiting uii 
Lowering Ships* Boats. — This recent invention, which is generally 
considered to offer many improvements to the present-day 
methods of launching ships' boats, is the result of the ingenuity 
of two Greenock gentlemen, whose professional experience has 
brought them into intimate contact with all the difficulties 
which surround the general question of boat stow^age and 
launching appliances. 

Briefly described, the apparatus consists of an overhead girder 
framework, provided with trolleys or carriages, adapted to carry 
tlie boats from any posUio7i on the boat deck of a vessel, to any 
launcliiu*^^ or lowering position, either on the port or starboard 
side. 

Transverso girders are fitted overhead in suitable positions 
to lift the ])oats. and other girders are arranged fore and aft and 
supported by the transverse »:irders. Separate trolleys are arranged 
to nin 01) each of the two directive girder systems, and permit of 
all the boats being (piickly transported, and launched in the most 
suitable and available positions. 

A portion of the end of each transverse girder is pivoted, 
and made to hin;^^^ so tJiat the outer end of this pivoted portion 
is s^v^lnL!: downwards, and the inner end upwards. This arran^^e- 
rnent f)revents any ohstniction or jjrojection from the side of the 
vessel while in harbour. 

TIh^ girders are supported by vertical pillars from the deck 
which do not interfere with the free passage of the boats. 

The trolleys are opc^.rated by hand-power winches. 

Dc^tailed sketches and s})eeification may be secured on appli- 
cation to the patent'eei^. 




PATENT DAVITS. ETC. 



466^ 



Arnott's Paleiit Boat-lowering Apparatus. — Tlik cumlijuatioii 
conaists of two davit arma ])ivoti}tl in fijutsteps on the deck, 
ami L'omiGcted at theii> upper eiidu with a humoutal member to 
{orni one continuous frame, which iii appearanco resembles very 
closely that of the McEachnit! davit without tho operating 
mochaniam. 

The hei({ht of the structure is sufficient to manipulate two 
open boats of Class I. or one open boat of Class I. and two boats 
of Class II. 

Steel wire falls are led flora the upper blocks fitted to the hori- 
zontal member of the davit frame, to two f;uide blocks which are 
attached to the head of an extended frame above the winch. 

Tho winch is arranged with a double barrel, one portion for 
each fall ; the barrel is driven by a worm, and the worm wheel is 
worked by winch handles. 

The winch can be fitted with an electric motor if required, and 
the additional mechanism does not interfere with the hand 
^oarin^;, which is always kept in readiness for operating in case 
the electric power ia not available. 

The upper boat is suspended iu the davit frame, the lower 
boat bein;; stowed in ordinary chocks on tho deck. The first 
operation for releaalnt; the apparatus is to lift the lever of a special 
slip gear which connects the horiztmtal davit arm and the head 
of the extended winch standard. The ba^e of the davit is set 
well inboard of the centre of j^ravity of the boat, so that on 
roleasuig the slip, the davit gradually desceude until it rests on tlie 
deck. The boat is then adjacent to the ship's side and in a position 
to bo safely lowered into the water. 

Havin« despatched tho first boat, the operator winds up the 
falLi on the winch and by the same motion brings back the davit 
into the position for attaching tliereto the remaining boat or 
boats. 

A special device is provided to prevent the davit returning 
to its extreme inboard posititm when the vessel has an adverse 
list, by the introdnctittn of a special bridio which coutrtjls the 
apparatus and enables it to be always in a positiim for lowering. 

It is claimed by the Anwtt's Patents. Limited, of Abuhurtih 
Lane, Loudon, that the whole operation of launching a boat 
safely into the water from their apparatus can be controlled by one 
man. 

SD«]ling's Patent Boat Stowing and Launching Gear.— The 
primary object of this apparatus is tho provision of suitable 
racks of a special defiign to enable a largo number of boata to be 

2 H 



466 SHIPS' BOATS 

stowed on the upper or boat deck of a vessel, together with an 
arrangement of derricks and controls whereby the whole system 
of boats can be launched from either side of the vessel. 

It will readily be seen that the construction of deck casings 
would have to be considered in conjunction with the requirements 
of the derrick system of laimching boats. 

Each laimching set consists of a double control box, upon 
which two derricks are mounted. The platforms which surmoimt 
the top of the control box, give the appearance of turn-tables, 
and are erected side by side. 

The derrick arms are formed of steel tubes, the ends of which 
are splayed out to form yoke pieces. The lower ends of the yoke 
pieces are connected at opposite points to their respective turn- 
tables, and the upper ends of the arms are connected by a steel 
cross brace. 

The stresses which are transmitted to the derrick during the 
operation of lifting are also supported by an ordinary upright 
standard, from the base of which are fitted auxiliary jibs, braced 
together at their upper ends with stout horizontal tie-rods. 

Each system of derricks is operated by independent motors, 
worked from an emergency power plant placed on the upper 
deck. 

The wire topping lifts pass over sheaves provided at the upper 
ends of the auxiliary jibs, and down over sheaves fitted at the 
centre of the tiim-tables to the winding drums arranged within 
the control box. 

Passengers can take tlieir places in the boats when the latter 
are stowed in their supporting racks or chocks ; the large operating 
derricks then ])ick iij) the loaded boats from their stowing positions 
on deck and transfer tliein to the water. Special disengaging 
uear is fitted to the boats to enable simultaneous release to take 
place at each end of the boat. 

in case of breakdown of the electric power, the gear can be 
operated by hand. 

The writer has not had the opportunity of witnessing a demon- 
stration of this invention, and the brief descriptive outline of the 
a})paratus has been gathered from information obtained from 
Snelling's Marine Patents of Tokenhouse Buildings, London, E.C. 

The Quixo Davit and Engineering Co. are weU known in 
Great Britain for their special design of davits and turning-out 
gear, but space will not permit of making detailed reference to 
their equipment. 



PATENT DAVITS, ETC. 



467 



The author has endeavoured to avoid expressing any opinion 
on the design of the various launching apparatus which would 
create an impression for possessing a partiality for a particular 
gear. The purpose of including so many patent appliances 
is to give the reader a general idea of the details and various 
methods which are now in operation on board vessels in Great 
Britain and the United States of America, and designed for the 
purpose of safely laimching ships' boats in the most expeditious 
manner. 



APPENDIX 

A. Instructions for the construction of life-rafts. 

B. Instructions for tlie construction of buoyant apparatus. 

C. Syllabus for technical instruction in boatbuilding. 

D. Table of squares and cubes. 

E. Decimals of a foot for each one sixty-fourth of an inch. 

F. Decimals of an inch for each one sixty -fourth of an inch. 

G. Approximate freeboard of Class I., open boats. 



A. COPY OF CIRCULAR INSTRUCTIONS, No. 1586, ISSUED BY 
THE MARINE DEPARTMENT OF THE BOARD OF TRADE 
IN NOVEMBER, 1917. 

Bif 'permission of the Controller of His Majesty's Stationery Office. 

LIFE-RAFTS. 

Cleneral Rule 2 of the Life-saving Appliances Rules provides that 
when one or more life»^rafts are accepted in lieu of a lifeboat, such 
life- rafts must be in every respecjt as efficient as the pontoon life-raft 
dascribed in General Rule 10. 

Life-rafts must be of a tyi)e approved by the Board and should 
be constructed under the supervision and to the satisfaction of the 
Surveyors. 

Before the construction of a new type of life-raft is commenced, 
a specilication and a fully detailed drawing of the raft, accompanied 
by a report from the Surveyor, should be submitted to the Board 
for approval. 

A raft, when completed, will be subjected to such tests of efficiency 
as th(\ Board may direct, and will be required to be in all respects 
satisfactory before being accepted as an approved life-saving 
appliance. 

The Surveyors are to be guided by the following instructions 
which interpret the sections of General Rule 10. 

The following paragraphs numbered I. to V. apply to life-rafts 



470 SHIPS' BOATS 

the construction of which is commenced after the Ist January, 
1918 :— 

I. Bulwarks. — The bulwarks must admit of easy erection and 
the arrangements for supporting them are to be strong and efficient. 
The bulwarks and their supports must not be liable to be broken 
or rendered unfit by the raft being thrown into the water from the 
height required by these instructions. The bulwarks are not to be 
less than 18 in. in height above the top of the platform. 

II. Size, weight, strength and materials. An approved life-raft is 
required to be of such size and weight that it can be handled without 
mechanical appliances, and accordingly the weight of a life-raft in 
pounds, exclusive of equipment, is not to exceed the perimeter of 
the raft in feet measured on the line of the hand-holds, multiplied by 
42, with a maximum of 15 cwts. 

A sample life-raft of each type and size adopted, and at least 
one in every ten similar rafts completed, is to be tested for strength 
by being dropped into the water on a deck, as well as on a side and 
end, in the presence of a Surveyor. 

In the case of new rafts the height from which the raft is dropped 
is to be not less than the height of the deck on which it will be stowed 
above the vessel's highest continuous deck, or 30 feet, whichever is 
the great-er. The height for the drop test is to be measured in each 
case from the lowest point of the raft to the water. 

It is desirable that the builders satisfy themselves r^arding the 
strength by subjecting the raft to private tests before complete 
official tests are witnessed. 

Rafts should be constructed of materials which do not quickly 
deteriorate by exposure to weather. If, however, the Surveyor is 
of opinion that the orii^inal strength of a raft has been materially 
reduced by exposure to the weather for a long period, or for any 
other reason, he should recjuire the drop test to be repeated, but in 
such cases a drop equal to three-fourths the height specified above 
may be regarded as sutlieient. 

An approved life-raft must be able to withstand the drop tests 
without Ijeing materially damaged. The Surveyor should carefully 
examine the raft after the test, and should inspect the air-cases, if 
fitted, for signs of distortion or leakage. 

All life-rafts are to be fitted with hand-holds or other means of 
lifting ; and the Surveyor should satisfy himself that such rafts 
ran be lifted and carried to the vessel's side with reasonable ease. 

Life-rafts are to be so constructed that they may be easily 
launched over the vessel's side ; and there should, therefore, be no 
projections on a raft which would seriously hamper the operation 
of sliding it over the rail or gunwale. 

III. Buoyanaj.— The buoyancy of life-rafts is to be provided 
by means of air-cases or by some method of equal efficiency approved 
))y the Board. If air-cases are fitted they are to be of copper or 



APPENDIX 



471 






yellow metal of not less than 18 oiw. per square foot, or of equally 
durable material, properly strengthened by a wood transverse frame, 
and coDHtructed generally as required for internal buoyancy for open 
lifeboats as prescribed in the Board's Instructions as to the Con- 
struction of Wooden Lifeboats (Circular 1575). The air-cases are 
to be easily accessible for periodical inspection. 

The required capacity of air-cases stated by the Rule is the 
minimum ; a much larger capacity may be necessary to comply with 
the requirements of paragraph 1 (iv.) of General Rule 10, 

I\'. Plalform, coTulnteiion and heif/lit of. — The platform or deck 
is to be such as to provide a proper foothold for the persons upon it. 
Where the doclc is close-planked, moans are to be provided for quickly 
dmiiiinn water ofi the deck, 

A sample lite-raft of each pattern adopted is to be weighed and 
the freeboard to the top of the platform is to be ascertained, the raft 
being loaded with weights equivalent to the number of persons for 
whom the raft is deemed sufficient, at 165 lbs. for each person, anil 
to the equipment. Unless the Surveyor is satlsliod that the platform 
of the raft when loaded will be more than 6 in. above the water level, 
and the weight of the raft less than the limit allowed by these Instruc- 
tions, these testa should be repeated tor at least one in every ten 
similar rafts constructed. 

V. lilabililtf and (e»t».— An approved lite-raft must have a 
sufficient margin of buoyancy and stability when laden with the 
equipment and the number of persons for whom it is deemed 
sufficient. 

A specimen of every new type of life-raft is to be inclined in the 
presence of a Surveyor in order that the stability of the raft may 
be ascertained. The raft when inclinedshould be in service condition 
and laden with metal weights equivalent to the total number of 
persons, at 165 lbs. for each person, and to the equipment, and the 
weights should be disposed vertically on the assumption that the 
centre of gravity of the occupants of the raft will be 2 ft. above 
the top of the deck or platform. 

VI. Equipment. — Proper means ate to be fitted for stowing the 
equipment of each liJe-raft, as required by General Rules 14 (3), 
11 (5), and loose articles of equipment are to t>e securely attached to 
the raft in such a way that the proce,sa of launching will not cause the 
loss of any of them. 

If provision and water tanks are fitted in the raft they should 
be accessible from either side ; special regard should be given, 
however, to the strength and watertightness of the covers, which 
should be carefully screwed up before a drop test is made. 

The length of boat hook and oars need not exceed the maximum 
inside dimension of the det^k. Rowing crutches should be of special 
pattern so that the raft c«n be easily rowed. For this purpose the 
height of the oar in the crutch should not be less than 12 in. abova 



472 SHIPS' BOATS 

the deck, and holes with lacing eyes should be provided in canvas 

bulwarks at this height. 

A double row of life-lines should be strongly secured all round 
the raft, the loops being of such a length that the floats of the upper 
row will be on the surface of the water at whatever draft the raft may 
be floating. 

VII. Slings. — Life-rafts are to be fitted with strong slings or 
strops and strong eye-bolts so that, if circumstances permit, they 
niav be lowered bv means of davits, cranes, or derricks. If the raft^ 
are not stowed under davits, cranes or derricks, a strong X-shaped 
bollard is to be provided abreast of each raft station. 

VIII. EriMituj life-rajts. -As regards life-rafts already con- 
structed, or of which the construction was commenced before the 
issue of these Instructions, the Surveyors should note that, while the 
foregoing explanatory paragraphs I. to V. may not strictly apply, 
no life-raft is in future to be accepted as part of the statutory equip- 
ment of a vessel unless it satisfies the conditions of General Rule 1^ 
or unless it has been apj)roved by the Board as being in every respect 
as (efficient as the life-raft described in that Rule. 

IX. Markimj. —\\'\\Q\\ the Surveyor has satisfied himself that the 
construction of a life-raft is in all respects satisfactory, he is to see 
that the raft is permanently marked as required by the Rules. 
The Surveyor should then complete the marking with his oflicial 
stamps by adding his initials, the date, etc. 

X. Stomif/e of life-rafts. --The Surveyors should note that 
General Kule 12 requires, inter (ilia, that raft« shall be stowed in 
such a way that they can be launched in the shortest possible time. 
Time and circumstances may in some cases permit of rafts being 
lowered into the water by means of davits or cranes, but in other 
circunistances it mav bo necessary to throw the rafts overboard. 
and it is (iesirable that provision should be made for both these 
methcKJs of launrhin^'. Kafts must also be stowed securolv but in 
such a manner that tliev ran (luicklv be made free to Hoat off the 
vessel in ease of sudden founderinu. A raft which does not exeee<l 
the \veii:lit specitird in these instructions may be stowed inboanl 
provided there i^ suiiicient surrounding space to enable it to be lifted, 
and that there i^ no ol>stru( tion wliich would prevent the raft Ikmuh 
carried \o the ships side with reasonable ease. 

SubjtM t to the forciiiunir paraiiraph, rafts not exceedin^r the weijiht 
s]>ei itied may l>e stowetl one upon another, but they are not to Ik» 
stowed thn^e in a heiizht un!c>s .-special appliances are tittinl for 
handiini: thetn an<l unle>s the arrani^ements have first reoeivotl the 
Board > approval. 

Ilatt-- are to be properly semretl bv ^rripes haviiu; slip links, or 
in MMue »s(ually eihri.MU niai\ner, and where one raft is stoweil alu^ve 
another the arra!\i:eiMent- >lK»uld be sueh. if practicable, that the 
release v»t a vin;:le set of irripes will set frtv lK>th rafts. 




APPENDIX 



473 



I 



iDB are to be fitted, in the form of eant« bolted to the 
deck or otherwise, to prevent tUc rafts moving transversely, or in a 
fore-and-aft direction, owin^; to the heeling or trimming of the vessel 
after the gripes have been removed. When one raft is stowed upon 
another, means must atao te fitted to prevent the upper raft sliding 
ofi the tower one after the gripes have been removed. 

Rafts should be provided with efficient covers to protect them 
from the weather. 

XI. Cmijicale of approval. — If a pontoon life-raft is constructed 
and equipped in the manner indicated in paragraphs numbered I, to 
VII., tested in accordance with paragraphs II. and V. of these instruc- 
tions, with satisfactory reaults. and complies with the conditions 
described in General Rule 10 of the Statutory Rule.-*, the owner, if he 
desires it, may be granted a certificate of approval. 

The maker will be required to submit a detailed specification and 
drawings of the raft which, subject to the Board's approval. wiU be 
annexed to the certificate of approval. He will also be required to 
furnish the Board with 3(X) copies of the certificate, including the 
specification and drawings, for distribution to the Board'a Surveyors. 

The fee for a certificate is five pounds (£.5), and should be paid 
when app!i(aition is made {on form Surveys 6) for the official tests 
to be witnessed by tJie Surveyors. 



B. 



COPY OF CIRCULAR INSTRUCTION, No. 1587, ISSUED BY 
THE MARINE DEPARTMENT OF THE BOARD OF TRADE 
IN DECEMBER, 1917. 






of llw Vonlrolh-f nf UU Majcuh/s Slali; 
BUOYANT APPARATUS. 



/ Op-e. 



The Life-saving Appliances Rules require a Home Trade passenger 
shij» [-0 carry boat^, approved life-rafts, approved buoyant deck Meats 
or other aj»proved buoyant apparatus sufficient Ut aci'onitufKlate 
the whole or a proportion (according to the Class in which the ship is 
placed) of the total number of perMon» for which the ship is certified," 
(Jeneral Rule 15 defines " approved buoyant apparatus *' as 
follows : — 

Approved buoyant apparatus, whether buoyant deck spate, 
buoyant deck chairs or other buoyant apparatus, shall be 
deemed sufficient, so far as buoyancy is concerned, (or a jieraon 
or a number of persons to be ascertained by dividing the number 
of pounds of iron which it is capable of supporting in fresji water 
by 32. Such buoyant apparatus shall be of approved material 
and construction, and if it depends for its bunyani-y on air shall 
not require to be inflated before use, and shall be marked in such 
a way as plainly to indicate that it. is bnoyiint,nnd the number 
of persons fur which it is approved. 



SHIPS' BOATS 

The followrng instructions havp been ])repared for the guidao 

of Surveyors in giving effect to this (Jeneral Rule. 

L — New Buoyant Apparatus, 

The following inatructiona apply to all buoyant apparatus whi 
may be supplied on or after July Ist, 1918 ; — 

(1) Comlitiong of approval. ~ -H the apparatus is not of a ty 
that haa previously received the Board's approval a full report i 
itM deaif^n and construction should be aubniitted to the Board by t 
Surveyors at the port, where a sample apparatus is to be nmde oi 
tested. 

Before approval can be given, detailed drawings and fi 
particulars muat be submitted, together with the results of the tm 
for flotation, stability and strength and such other tests as the Bos 
niay deem necessary. 

(2) Aocejilunce of ajiproved (ypes .^Apparatus of a type appror 
by the certificate of approval subsequently to the iasue of the 
Instructionfi, and apparatus of a type 'named in the list given 
Section VI., may be passed if the Surveyor is satisfied that it coi 
plies in all respects with the specification annexed to the certifies 
and that the materials and workmanship are satisfactory, SampI 
of such apparatus should, however, occasionally be tested f 
strength, flotation, and stability as opportunities occur. 

(3) Types lioi on list but previotuly approved. — ^If the apparai; 
is not included in the list in Section VI., and does not comply wi 
the following requirements, but has at some time received the Board 
approval, the Surveyor should forward a full report, giving all the 
informatibn required in the case of a new type, 

(4) Malerial awi workmanship. — The materials and workman- 
sjiip in the construction of all buoyant apparatus are to be of 
best quality, and the Surveyor should satisfy himself by freqi 
inspection during the construction, that these conditions 
fuimied. 

In any cases of doubtful efficiency the Surveyor should requi] 
such teats as he may consider necessary to ensure that the apparaf 
shall be reliable. 

(5) Apparatus which requires aitjudjitenl. — No apparatus 
requires adjustment is to be accepted, nor any which reqi 
preparation, apart from the cutting adrift of the deck lashings, 
these are fitted. 

(6) Automatic locking tkvtces. — Apparatus which is intended 
open out automatically when placed in the water is liable to 
objection that the hinges or other working parts are likely to ' 
inefficient. Special tests will be required, and such apparat 
should not be passed unless the Board's special sanction has 
been received, 

(T) Slalnlity.—lt is important that buoyant apparatus ehoi 



APPENDIX 



475 



I 



i 



have sufficient stability in iiny position in which it is capable of 
floating, and no buoyant appaiutus supplied to a vessel on or after 
July Ist, 1918, is to be accepted unless it in capable of supporting 
a weight of iron, suspended in the water from the life-lines, of 15 lbs. 
per ft, length, along any edge, without capsizing. If, however, 
the length of the edge is 4 ft. 3 m., or leas, the nunimuui weight of 
iron suspended from any edge should be 64 lbs. When reporting 
the result of a stability test, the Surveyor should atate the angle to 
which the apparatus inclined when loaded as above. The conditioiiB 
of thiB test will be subject to modification in the case of an apparatus 
intended tu support a much smaller number of persons than the 
perimeter of the apparatus measured in feet. 

(8) Constntdion of air-cusf-ii. — If the buQyancy is provided bv 
metal air~cases. theae are to be constructed as described in para- 
graph H of the luHtructiouH relating to the construction uf wooden 
life)>oBts (Circular lf)7Q]. Air-cases are not to be more than 1 ft. in 
length, and, when more than 3 ft. 6 in, In length nr breadth, they 
are to be efficiently stiffened Ijy divisions or stays. The cases are 
not to be pierced for the attachment of wootl diviaioos or stays or 
for any other purpose. 

The air-cases should be protected from injury by properly fitted 
wood casing or sparring, easily removable for the pnriodical inspection 
of the air-cases by the Surveyor, and should be secured against 
movement within the casing. 

No iron work is to be placed in contact with metal air-cases. 

If it is desired to provide the buoyancy otherwise than by metal 
air-cases as above described, full particulars of the proposal are to 
be submitted and the Board's approval obtained before any apparatus 
so fitted It passed by the Surveyor. 

(9) Life-lines. — Life-lines are to be fitted all round the apparatus 
having a number of equal loops corresponding to the number of 
persons for which the apparatus is certified. Each loop is to have a 
cork or light wood float, and the depth of the loop when wet should 
not be less than 6 in. and not more than 8 in. 

In apparatus of 12 in. or less in overall depth, one row of life-lines 
may be attached along the line of the middle pf the depth, but in 
apparatus of greater depth two rows of life-lines are to be fitted, one 
having its points of attachment a Uttle below the top of the air-cases 
and the other a little above the bottom of the air-cases and as close 
to the sides of the air-cases as is practicable. Jackstays or handrails 
are not to be substituted tor life-lines. 

The life-lines must be of durable material and each of the Hecurities 
of the life-lines should be strong enough to support the weight of the 
apparatus in view of the possible need for lifting or dragging the 
apparatus along the deck to the launching station. The screwed 
eyes which have sometimes been fitted for securing Ufe-lines have 
often been of insufficient strength. The Ufe-lines and securities 



t76 



SHIPS' BOATS 



sliouli! tliorefore lie subjected to sevece testinj; by the Surveyw 
before any buoyant apparatus w passed. 

(10) Maximum lOfiiflif.—Tho nmximmn weight of any b 
apparatus ia not to exceed 4()0 Iba. ; but when the weight e 
300 lbs. proper handle* or rungs should be fitted to facilitate t 
moving about of the apparatiLs. 

There must be do projections from the buoyant apparatus vhi 
would prevent the apparatus being slid easily over thi 
launching. 

(11) Strength le^ls. — Each new type of buoyant apparatus is ta 
be subjected to a teat of strengtli by throwing a sample into the 
water, and it must be of suflicieut strength to Bustain no injury aa 
a result of that test. If the buoyant apparatus ia for a specific 
vessel it should be thrown from the height of the deck on which it ia 
stowed, but all seats not allocated and for which a general approval 
is sought by the makers shoxild be tested by throwing a sample into 
the water from a height of 20 ft. (see paragraph 6). 

(12) Nuitiber of persons. — ^The number of persona for which any 
buoyant apparatus will be deemed suitable will be determined br 
the least oi the numbers ascertained as follows, subject to the reaoj 
of the stability test described above : — 

(u) The number of lbs. of iron which it is capable of support 

in fresh water dirided by 32. 
(6) The perimeter of the apparatus measured in feet along t 

line of the pointa of attachment of the lite-iines. 
If, however, the apparatus is designed to support- persons i 
such a manner that tUey are only partially immersed in t" 
water, or if facihties exist for climbing on to the top of the appi 
atus, the divisor stated in Kub-paragraph (a) may require to I 
increased. 

(13) 3f(wiins.— ^Vben the Surveyor has satisfied himself thalj 
new buoyant apparatiLs complies with the foregoing conditiona f 
should reiiuire it to be marked in accordani'e with (Jeneral Rule fl 
The marking should be on a side or end of the apparatus exposed fl 
the view of passengers aud should be a.s follows : - 

Buoyant Apparatus . . . Persons. 

The figures and letters denoting the number of persona should 
be permanently cut or branded into the woodwork of the apparatus, 
The Surveyor should complete the markiug by adding his initials, 
the date, etr., which should in every ease be stamped iinniediately 
below the figure denoting the number of persons. 

The issue of metal approval plates formerly in use for marking 
buoyant apparatus has b<>cn discontinued. When a buoyant 
apparatus, previously approved, is rejected as incfiieicnt, t>be approval 
plate, if still attached, should be returned to the Board with the 
Surveyor's report. 




Existing Buoyant Apparatus. 



Apparatus of a type meutioued in the list given iji Section VI. 
of theae Instructions wliicli bears au approval plate iaaued by the 
Board of Trade or baa been marked with a Surveyor's initials (see 
paragraph 13), may be passed ao long as it remains in good condition. 
Apparatus of other types which may previously have been 
approved and which bears an approval plate issued by the Board 
of Trade may be accepted an part of the statutory life-savinj! 
appliances of the ship for which it waa originally approved provided 
that (i) the Surveyor is satisfied after inspection that the apparatus 
is in all respects in good condition ; and (ii) that the apparatus, 
or a, precisely similar apparatus, liaa been Hubjected with satisfactory 
resulta to the stability teat spedfied in paragraph (7) of these Instruc- 
tions. The Surveyor should, liowever, forward full particulars of 
the case to the Board for instructions before rejecting any existiuj; 
apparatus for failure in the stability test. 

In everj- case in which apparatus previously approved is rejwted 
as iaelficient the approval plate, if still attached should be returned 
to the Board with the Surveyor's Report. 

Buoyant apparatus of old types which tail to fulfil the stability 
tei^ta may, 10 far as tti«ir condition allows, be used up cither by 
cisnversion iuto a new and satisfactory type, or by fast*nin^ two 
of tlkcm together securely to form a unit of stable apparatus 

UL — Stowage of Buoyant Apparatus. 

The immediate readiness fur use of all buoyant apparatus Is con- 
sidered to be of great iiii|>ort4ince, and Surveyors are instructed that 
special attention is to be <lirccte<l to tliis point. Aiiv case in which 
this condition is not fulfilled should be at once reporti^ to the Board. 

Buoyant apparatus are not to be stowed on top of deck houHCH 
or in other isolated positions from which they could not bo launched 
directly into the water, nor are they to be stowed below deck or in 
any deck erection. 

Buoyant apparatus must not be secured to the ileck, except by 
lashings which can be easily cut by aa ordinary pocket kulfc. They 
may be stowed in tiers one above the other, but must, iu that case, 
be kept apart sufficiently to prevent any possibility of their being ~ 
stuck together by paint or varnish, and must be supported on brass 
or hard wood distance pieces. 

Mc-aiis are to be provided, in the form of cAiits fastened to the 
deck or some other equally efficient arrangement, to prevent buoyant 
apparatus sliding across the deck, in the event of the vessel taking a 
list, or moving forward or aft if the veaael takes a heavj- trun by 
the bow or stern. 

Buoyant apparatus which axe atowed In tiers inuat also be fitted 



478 SHIPS' BOATS 

with dowels and sockets or some other efficient means for prevent! 
apparatus in an upper tier from sliding ofi a lower tier. 

IV.— Inspeetlon of Buoyant Apparatus. 

The buoyant apparatus are to be carefully inspected by t 
Surveyors at every annual survey of a passenger steamer which 
equipped with these appliances, in order to ascertain that they a 
in good condition and in all respects efficient. Special attentii 
should be given to those forms of apparatus in which there are ai 
hinges, joints, mechanical contrivances or working parts of ai 
description, and it will be the dut}' of the Surveyor to report to t 
Board, at once, any failure or defect which may be found at t 
periodical surveys. 

The air-cases of buoyant apparatus are to be periodically test 
for watertightness, and, in general, the cases of not less than on 
fifth of the total number of apparatus in the vessel are to be 
tested at each annual survey. If the Surveyor is of opinion that 
is necessary to remove the air-cases from the apparatus for th 
purpose, they should be removed and carefully replaced after beii 
satisfactorily tested. 

V. — Certificates of Approval. 

The makers of a new type of buoyant apparatus which is foui 
to comply fully with the requirements indicated in Section I., pan 
graphs 4 to 12, of these Instructions may, if they desire it, be grante 
a Certificate of Approval in respect of such apparatus. 

If such a Certificate is desired, the makers will be required t 
submit a full and detailed specification of the apparatus, illu^tratec 
if necessar}% by drawings or photographs. In the event of a Certif 
cate of Approval being granted, the makers will be required to f urnis 
the Board with 3()0 copies of the Certificate and specification. 

The fee for a Certificate of Approval will be £5. 

VI. — List of Approved Buoyant Apparatus. 

Buoyant apparatas of the types named in the following list ma 
be regarded as complying with these Instructions, and should b 
dealt with in the manner indicated in Section I., paragraph 2. Th 
name of any buoyant apparatus approved by a Certificate of Approva 
subsequently to the issue of these Instructions should be added t 

the list : — 

(1) Adams' Patent Buoyant Apparatus. 
If (2) "C. & H." Deck Seat. 

(3) Carley Life Float. • 

(4) Crichton's " Unit " Buoyancy Apparatus. 

(5) Day, Summers, & Co.'s Buoyant Deck Seats (El and E2). 

(6) Iron's Deck Seat. 






APPENDIX 479 

(7) Linkleter*8 Buoyant Deck Seats (Types C and D). 

(8) Linkleter's Buoyant Apparatus. 

(9) Linkleter's " Twin Lifebuoy." 

(10) MacTavish Patent Automatic Buoyant Deck Seat. 

(11) " Perry & Chambers " Single and Double Deck Seats (W. 

Gradwell & Co.). 
(12)* " Quidos " Buoyant Deck Chair (hammock type). 

vn. — Foreign-going Passenger Ships. 

Buoyant apparatus does not form part of the statutory equip- 
ment of a foreign-going passenger ship. During the war, however, 
it was most desirable that every such ship should carry, in addition to 
the life-saving apparatus required by the statutory Rules, life-rafts, 
or some form of buoyant apparatus which would be free to float 
clear in a case of sudden foundering such as might have occurred 
when a vessel was torpedoed or mined. Such apparatus need not 
necessarily comply with General Rule 15 or with these Instructions. 
Surveyors should, if desired by shipowners or masters, give whatever 
assistance they can with regard to the provision and suitable 
stowage of such apparatus. 

VIII. — Cancellation of Previous Instructions. 

Circular 1529 regarding the substitution of life-jackets and 
lifebuoys for buoyant apparatus is hereby cancelled and the arrange- 
ment set forth in paragraph 3 of that Circular will cease to have 
effect on the 1st January, 1919. 



C. SYLLABUS FOR TECHNICAL INSTRUCTION IN BOAT- 
BUILDING. 

During the recent war a revival of interest took place in boat- 
building, mainly due to the regulations of the Board of Trade 
insisting on a standard specification being recognised throughout 
Great Britain, and also to the increased demand for lifeboats. 

Previous to the year 1917 the most important of the yacht and 
boat builders well known for their high standard of workmanship 
and efficiency, were imable to compete under the prevaiUng con- 
ditions at that time. 

The trade has recently received a fresh impetus, and it is 
generally considered that better opportunities should be given 
apprentices to understand the details of construction of the various 
types of boats, and the associated theoretical considerations. 

There has been a tendency on the part of some firms to secure 

* Deck chairs do not come fully within the range of these Instructions. 
" Quidos " deck chairs may be passed if they are in aooordanoe with the 
speoifioation annexed to the certificate of approval, and if they are in good 
condition. 



4811 



SHIPS' BOATS 



tliP assistance of boys for Ilie sole purpose of obtamiiig cbeujj labour, 
with the inevitable consetjuence that the boys have recicived a 
very inefficient training. 

To obviate the diffirultiea referriKl to, the boatbuilders of the 
Ureenock diatrirt have given their hearty co-operation and aynipatliy 
to & scheme for the syBtematic education of their apprentices, and with 
the assistance of the local edue&tion authority, a boatbuilding class 
was commenced in 1917 with aatisfact«ry results. 

The lollowing syllabus was drawn up by the writer for the 
guidance of students : — 

Stage I, 

MulfHals tmcd tw Cotutntdion. — Explanation of the various 
kinds of timber used in boatbuilding, their (lualities, ((rowths, defects, 
diaeaHea, methods of seasoning and preserving. Wrought iron, steel, 
copper, munta metal, their respective quahtics and where used in 
the structure of a boat. 

Tool*- — Kxplaustion of various kinds used, openttioiis performed 
by each, and the importance of exercising care iu their upkeep. 

tniclKol BoiUbuildimj. — Details of building foundation, method 
of plumbing stem, etc. Explanation of details of combination, 
keel, keelson. Log piece, stem, sternpust, apron, and deadwood. 
Various kinds of scarphs used, and means of security. General 
deseription of process of plaukiiig, and difference in " clinker " and 
" carvel " methods. The use of the steam cheat. The method of 
timbering. Details of the various fastenings, where and why used. 
Thwarts and side seats, how secured. Buoyancy air-cases, why 
iitted, and how constructed. Various types of gunwales and how 
constructed. Breasthooks and floors, where useil and how secured. 
Stopwaters, where and how fittetl. Use of lower seats, numbe 
required, aud method of fitting. Plugs, where and how 
Details of stretchers, bottom boards, and gangbourds. 



Stagk II. 

MutLfhila, til:- Iron. Hteel, uiid various metals us 
building, their composition, mid tests to which they 
subjected. Comparative strength and suitabihty of various kinds 
timber (or boatbuilding, and where used m the structure. Bxpli 
tiou of sap, wet and dry rot, maturity, conversion, and proper ' 
for felling timber. 

Praclicai BoatbiiiUiw). — Explanation of the various classes of 
lifeboats. Difference in detail between the open aud pontoon 
lifeboats. Moulds, where used, and why. Lifting hooks and their 
keel connections. Square-stcmed boats, details of working tTansom 
and method of tilting quarter badges. Precautions taken wl 
using larch for planking. Suitabihty of using various gauges 



■rm 





APPENDIX 



481 



Lfasteninga. Detaib oE rudders. Mctbod of eecuring jstem and 
Is. Life-linea, how secured. Details of fenders and how 
Kiured. Details of iua»t steps, hasps, etc. Method of measuring 
t capacities and buoyancy air-cases. Details of oiasts. 
Theorij. — Drawing to scale simple parta of the structure of a 
lifeboat, and enlarging from one scale to another. Calculation of 
volumes and weights of simple aolids. 

Stage III. 

Mall-rials, i^fc. ^Procedure taken in selecting timber and method 
of measuring. Comparative cost of various woods. Explanation 
nf markings on foreign timber. 

Workshop 3/rtcAinery. ^Explanation of the general equipment of 
a boat-yard. Circular saw, band saw, planing and sandpapering 
machine, spindles, etc. : their particular uses, methods of working, 
care of upkeep, dangers in working, and means adopted for protecting 
operators. 

Praclical £l(M(^'UlY(/^H</. ^Treatment of defects found in lifeboats 
as a result of wear and tear, and methods of repairing damage. 
Details of steel and nested boats. Methods of working double-skin 
planking. Details of engaging and disengaging gears. Boat stowage 
arrangements, and launching apparatus. Sail and rigging plana. 
Details of construction of pontoon and Class 11a open lifeboats. 
Details of towing bollards. Caulking and painting. Details of 
equipment and how stowed. The construction of motor launches, 
and precautions taken for the safety of passengers. Spar and oar 
making. Suitable scantlings for various types of boats. Methods of 
galvanising. 

Theory. — Explanation of rules for Life-saving Appliances, the 
infiuence of form on stability. Suitable dimetisions for ships' boats. 
Explanation of the terms : stress, strain, shearing force, elastic limit, 
bending moment, buoyancy, displacement, centres of gravity and 
buoyanc)-, inclining experiment. Sheer plan, and method of fairing 
( tip a set of lines. Methods of making and setting up moulds. 




482 



SHIPS* BOATS 



(D) TABLE OF SQUARES AND CUBES OF NUMBERS UP TO 

45. RISING BY 0'05. 



g 


in 
o 


Cubes. 


2 

s 


uares. 


Cubes. 


1 


i 


CDbea. 


s 


C 1 






c 




•^ 


c 




V; 


*J 




2-05 


CO 

4 




ST. 

4-05 


OQ 

i 

i 16 


r 


0*05 


9 


66 


010 


. — 




2-10 


4 


9 


410 


1 17 


1 69 


015 




— 


215 


5 


10 


4-15 


! 17 


1 71 


0*20 




— 


2-20 


5 


11 


4-20 


18 


74 


025 


- 




2*25 


5 


11 


4*25 


18 


77 


030 


- - 


- 


2-30 


5 


12 


4-30 


18 


80 


0-35 


^ 


- - 


2-35 


6 


13 


4*35 


19 


82 


0-40 






2-40 


6 


14 


4-40 


19 


85 


0-45 


■ - 


- - 


2-45 


6 


15 


4-45 


20 


88 


0-50 






2-50 
2-55 


6 
7 


16 
17 


4*50 
4-55 


20 
21 


91 


0-55 


94 


0-60 






2-60 


7 


18 


4-60 


21 


97 


0-65 


— 


— 


2*65 


7 


19 


4-65 


22 


101 


0-70 


.. _ 


• - 


2-70 


7 


20 


4-70 


22 


104 


0-75 




- ■ 


2-75 


8 


21 


4-75 


23 


107 


0-80 






2-80 


8 


22 


4-80 


23 


111 


0-85 






2-85 


8 


23 


4-85 


24 


114 


090 






2-90 


8 


24 


4-90 


24 


118 


0-95 






2-95 


9 


26 


4-95 


25 


121 


1-00 






3-00 
305 


9 
9 


27 
29 


5-00 
5-05 


25 
26 


125 


105 


129 


1-10 


1 




3-10 


10 


30 


510 


26 


133 


115 




2 


315 


10 


31 


515 


27 


137 


1-20 




2 


3-20 


10 


33 


5-20 


27 


141 


1-25 


2 


2 


3-25 


11 


34 


5-25 


28 


145 


1-30 


2 


2 


3-30 


11 


36 


5-30 


28 


149 


1-35 


2 


2 


3-35 


11 


38 


5-35 


29 


153 


1-40 

1 


2 


3 


3-40 


12 


39 


5-40 


29 


157 


1-45 ' 


2 


3 


3-45 


12 


41 


5-45 


30 


162 


1-50 


2 


3 


3-50 


12 


43 


5-50 


30 


166 


1-55 


2 


4 


3-55 


13 


45 


5-55 


31 


171 


1-60 


3 


4 


3-60 


13 


47 


5-60 


31 


176 


1-65 


3 


4 


3-65 


13 


49 


5-65 


32 


180 


1-70 


3 


5 


3-70 


14 


51 


5-70 


32 


185 


1-75 


3 


5 


3-75 


14 


53 


5-75 


33 


190 


1-80 , 


3 


6 


3-80 


14 


55 


5-80 


34 


195 


1-85 


3 


6 


3-85 


15 


57 


5-85 


34 


200 


1-90 


4 


7 


3-90 


15 


59 


5-90 


35 


205 


1-95 


4 


7 


3-95 


16 


62 


5-95 


35 


211 


200 


4 


8 


4-00 


16 


64 


6-00 


36 


216 





1 








APPENDIX 




_i: 


1 


Cabas. 


1 


1 


CnbM. 


1 


1 


- 1 


6-OS 


37 


221 


B-56 


73 


625 


1105 


122 


^1 


«-I0 


87 


227 


8-60 


74 


636 


1110 


123 


1.368 ■ 


616 


38 


233 


8-85 


75 


647 


11-15 


124 


1.386 ■ 


e-20 


38 


238 


8-70 


76 


659 


11-20 


125 


1,405 H 


a-26 


38 


244 


8' 75 


77 


870 


11-25 


127 


1.424 ■ 


S-60 


40 


250 


8-80 


77 


681 


11-30 


128 


■ 


8-36 


40 


ase 


885 


78 


693 


11-35 


129 


1,462 ■ 


6-40 


41 


262 


8-90 


79 


705 


11-40 


130 


1.482 ■ 


6-45 


42 


288 


8-95 


80 


717 


11-45 


131 


1,501 H 


6-60 


42 


275 


9-00 


81 


728 


11-50 


132 


■ 


6-66 


43 


281 


9-05 


82 


"741 ~ 


11-56 


133 


■ 


8-60 


44 


287 


9-10 


83 


754 


11-60 


135 


1.561 V 


e-65 


44 


294 


B-15 


84 


766 


11-65 


136 


1.581 ™ 


6-70 


4G 


301 


B-20 


85 


779 


11-70 


137 


1,602 


6-76 


46 


308 


S-25 


88 


791 


11-75 


138 


1,622 


6'SO 


46 


314 


9-30 


86 


804 


11-80 


139 


1,643 


S-Sfi 


47 


321 


9-35 


87 


817 


11-85 


140 


1,664 


e-M 


48 


329 


8-40 


88 


831 


11-90 


142 


1,685 


ft-B6 


48 


336 


9'45 


89 


844 


1185 


143 


1,706 


7*00 
7-06 


48 


343 
350 


fl-50 
9' 55 


90 
91 


857 

87) 


12-00 

12-05 


144 

145 


1,728 
1,750 


50 


7-10 


M 


358 


960 


92 


885 


12-10 


146 


1.772 


7- IB 


61 


366 


9' 65 


93 


899 


12-15 


148 


1,794 


7-ao 


62 


373 


9-70 


94 


913 


12-20 


149 


1.816 


7-26 


63 


381 


9' 75 


95 


927 


12-25 


150 


1,838 


7-30 


68 


389 


9' 80 


96 


941 


12-30 


151 


1,861 


7-36 


64 


397 


9-85 


97 


956 


12-35 


153 


1.884 


7-40 


66 


405 


9-90 


93 


S70 


12-40 


154 


1.907 


7-46 


66 


413 


9-95 


99 


985 


12-45 


155 


1.930 


7-60 


56 


422 


10-00 


100 


1.000 


12-50 


156 


1.963 


"7-M 


~57 ' 


430 


10-05 


101 


1.015 


12-55 


158 


1.977 


7-eo 


68 


439 


10-10 


103 


1,030 


12-60 


159 


2.000 


7-66 


69 


448 


1015 


103 


i,04a 


12-65 


180 


2.024 


7-70 


69 


457 


10-20 


104 


i.oei 


12-70 


161 


2,048 


7-76 


60 


465 


10-25 


105 


1,077 


13-75 


163 


2.073 


7-80 


61 


475 


10-30 


106 


1.093 


12-80 


184 


2,097 


7-te 


62 


484 


10-35 


107 


1.109 


12-85 


185 


2,122 


7-90 


62 


493 


10-40 


108 


1.125 


12-90 


166 


2.147 , 


7-B5 


63 


502 


10-45 


109 


1.141 


12-95 


.68 


2.172 


8' 00 


64 


512 


10-50 


110 


1.158 


1300 


109 


2.197 


8-OS 


B& 


522 


10-55 


III 


1.174 


13-05 


170 


2.222 


8-10 


66 


531 


10-60 


112 


1.191 


13-10 


172 


2,248 


8-16 


66 


641 


io-a5 


113 


1,208 


13-15 


173 


2,274 


g-20 


67 


551 


10-70 


114 


1.225 


13-20 


174 


2.300 


8-2S 


68 


562 


10-75 


lis 


1.242 


13-25 


176 


2.326 


8-80 


6ft 


672 


10-80 


117 


1,260 


13-30 


177 


3,353 


8-36 


70 


582 


10-85 


118 


1.277 


13-35 


178 


2.379 


»40 


71 


593 


10-90 


119 


1.295 


13-40 


180 


2.406 


8-46 


71 


603 


10-95 


120 


1.313 


13*5 


181 


2.433 


»M 


78 


614 


11-00 


121 


1.331 


13-50 


182 


2,460 


I" 









4»1 



SfflPS' BOATS 



5 


y 
« 
»• 

« 


Cab«. 


i 

* 


< 

3 


Cnbo. 


S 


1 


c*b«. 


£ 


-f. 




z 


X, 




sE 


* 




13-55 


184 


2.488 


16-05 


258 


4,135 


18-55 


344 


6,383 


13-60 


185 


2^15 


16-10 


259 


4.173 


18-eo 


346 


6,435 


13-65 


186 


2,543 


16-15 


261 


4,212 


18-65 


348 


6,487 


13-70 


188 


2^71 


16-20 


262 


4,252 


18-70 


350 


6.539 


13-75 


189 


2.600 


16-25 


264 


4,291 


18-75 


352 


6,5« 


13-80 


190 


2,628 


16-30 


266 


4,331 


18-80 


353 


6J45 


13-85 


192 


2,657 


16-35 


267 


4,371 


18-85 


355 


6,6M 


13-90 


193 


2,686 


16-40 


269 


4.411 


18-90 


357 


6.751 


13-95 


195 


2.715 


16-45 


271 


4,451 


18-85 


359 


6,805 


14-00 


196 
197 


2,744 
2,774 


16-50 
16-55 


272 
274 


4,492 
4,533 


19-00 
19-05 


361 


6850 


14-05 


363 


6,913 


14^10 


199 


2.803 


16-60 


276 


44»74 


19-10 


365 


6,988 


14^15 


200 


2,833 


16-65 


277 


4,616 


19-15 


367 


7.023 


14-20 


202 


2,863 


16-70 


279 


4,657 


19-20 


368 


7,078 


14-25 


203 


2.894 


16-75 


281 


4,699 


19-25 


371 


7.133 


14-30 


204 


2,924 


16-80 


282 


4.742 


19-30 


372 


7,189 


14-35 


206 


2,955 


16-85 


284 


4,784 


19-35 


374 


7.845 


14-40 


207 


2,986 


16-90 


286 


4,827 


19-40 


376 


7481 


14-45 


209 


3.017 


16-95 


287 


4,870 


19-45 


378 


7,358 


14-50 


210 


3,049 


1700 


289 


4,913 


19-50 


380 


7.415 


14-55 


212 


3.080 


17-05 


291 


4,956 


19-55 


3^ 


7^472 


14-60 


213 


3.112 


1710 


292 


5.000 


19-60 


384 


7,530 


14-65 


215 


3.144 


17-15 


294 


5.044 


19-65 


386 


7,587 


14-70 


216 


3.177 


17-20 


296 


5,088 


19-70 


388 


7,645 


14-75 


218 


3.209 


17-25 


298 


5.133 


19-75 


390 


7,704 


14-80 


219 


3,242 


17-30 


299 


5,178 


19-80 


392 


7,762 


14-85 


221 


3.275 


17-35 


301 


5.223 


19-85 


394 


7,821 


14-90 


222 


3.308 


17-40 


303 


5,268 


19-90 


396 


7,881 


14-95 


224 


3.341 


17-45 


305 


6.314 


19-95 


398 


7,940 


1500 


225 


3,375 


17-50 


306 


5,359 


20-00 


400 


8,000 


1505 


227 


3,409 


17*55 


308 


5,405 


20-05 


402 


8,060 


1510 


228 


3.443 


17-60 


310 


5.452 


20-10 


404 


8,121 


1515 


230 


3,477 


17-65 


312 


5,498 


20-15 


406 


8,191 


15-20 


231 


3,512 


17-70 


313 


5,545 


20-20 


408 


8,242 


15-25 


233 


3.547 


17-75 


315 


5.592 


20-25 


410 


8,304 


15-30 


234 


3,582 


17-80 


317 


5.640 


20-30 


412 


8,365 


15-35 


236 


3,617 


17-85 


319 


5,687 


20-35 


414 


8,427 


15-40 


237 


3,652 


17-90 


320 


5,735 


20-40 


416 


8,490 


15-45 


239 


3.688 


17-95 


322 


5,784 


20-45 


418 


8,552 


15-50 


240 


3.724 


18-00 


324 


5,832 


20-50 


420 


8,615 


15-55 


242 


3,760 


18-05 


326 


5,881 


20-55 


422 


8,678 


15-60 


243 


3,796 


18-10 


328 


5,930 


20-60 


424 . 


8,742 


15-65 


245 


3.833 


18-15 


329 


5,979 


20-65 


426 


8,806 


15-70 


246 


3,870 


18-20 


331 


6,029 


20-70 


428 


8,870 


15-75 


248 


3.907 


18-25 


333 


7,078 


20-75 


431 


8,934 


15-80 


250 


3.944 


18-30 


335 


6.128 


20-80 


433 


8,999 


15-85 


251 


3,982 


18-35 


337 


6.179 


20-85 


435 


9,064 


15-90 


253 


4,020 


18-40 


339 


6,230 


20-90 


437 


9429 


15-95 


254 


4,058 


18-45 


340 


6,280 


20-95 


439 


9.195 


16-00 


256 


4,096 


18-50 


342 


6,332 


21-00 


441 


9,261 



i 


1 


Cub*.. 


1 


j 


Cub«». 


1 


i 


Ciib«a. 








^ 


" 




X 


TO 




21-06 


MS 


9.827 


23-65 


666 


13.061 


26-06 


670 


17,878 


2110 


445 


9,304 


28-60 


667 


13,144 


26-10 


681 


17.780 


2115 


447 


9.461 


28-66 


569 


13,228 


26-15 


684 


17,882 


21-20 


449 


9,628 


23-70 


662 


13,312 


26-20 


686 


17,986 


21-25 


452 


9,596 


23-75 


H4 


13.396 


26-36 


689 


18,088 


21-30 


454 


9,664 


28-80 


566 


13,481 


26-30 


602 


18,101 


21-3& 


4SS 


9,732 


28-85 


569 


13,666 


28-36 


604 


18,295 


21-40 


468 


9,800 


23-90 


57.1 


13,662 


26-40 


607 


18,400 


21- 4& 


460 


9,869 


23-06 


574 


13,738 


26-45 


700 


18,504 


21-50 


462 


9,938 


2400 


576 


13,824 


26-60 


702 


18,610 


11-56 


~464~ 


10.008 


24-05 


57S 


13,911 


26-65 


705 


18.716 


21-60 


467 


10.078 


24-10 


581 


13.998 


26-60 


708 


1S.821 


21-65 


460 


10,148 


24-15 


583 


14,085 


26-66 


•710 


18,927 


21-70 


471 


10,213 


24-20 


586 


14,173 


26-70 


713 


19,034 


21-75 


473 


10.239 


24-25 


588 


14,361 


26-75 


716 


19.141 


21-80 


475 


10.360 


24-30 


690 


14.349 


36-80 


718 


19.249 


21-85 


477 


10.432 


24-35 


593 


14.438 




721 


19,357 


21-00 


480 


10.603 


24-40 


595 


14.527 


26-90 


724 


19,465 


21-95 


482 


10.576 


24-45 


598 


14.616 


26-95 


726 


19,574 


'22-00 


484 


10.848 


24-50 


BOO 


14,706 


27-00 


729 


18,683 


22-05 


480 


10.72i, 


24-56 


603 


14.796 


27-05 


732 


19,703 


22-10 


488 


10.794 


24-60 


606 


14.887 


27-10 


734 


10,003 


22-15 


481 


10.867 


24-65 


808 


14.978 


3715 


737 


30,013 


22-20 


493 


10.941 


24-70 


810 


15,060 


27-20 


740 


20,124 


22-25 


495 


11,015 


24-75 


613 


16,161 


27-25 


743 


20,235 


22-30 


497 


11,090 


34-80 


616 


15.263 


37-30 


746 


20.346 


23-36 


500 


11,164 


24-85 


818 


16.345 


27-86 


748 


30.458 


22-40 


602 


11,239 


24-90 


820 


15,438 


27-40 


751 


20,571 


22-45 


604 


11,315 


24-05 


623 


15.531 


27-45 


754 


20,684 


22-50 


606 


11.391 


25-00 


635 


15.625 


27-50 


756 


30.707 


22-55 


509 


11,467 


25-05 


628 


15.719 


27-55 


759 


20,011 


22-60 


5il 


11,543 


25-10 


630 


15,813 


27-60 


762 


21.025 


22-65 


513 


11,620 


25-15 


633 


15,908 


27-65 


765 


21.139 


22-70 


616 


11,607 


35-20 


635 


16.003 


27-70 


767 


31.254 


22-76 


518 


11.776 


26-25 


638 


16,098 


27-75 


770 


31,360 


22-80 


520 


11,852 


25-30 


640 


18.194 


27-80 


773 


21,485 


22-85 


522 


11.930 


25-35 


643 


16.290 


27-85 


778 


31.601 


22-90 


624 


12.000 


25-40 


646 


16.387 


27-00 


778 


31,718 


22-85 


527 


12,088 


25-46 


648 


16.484 


2705 


781 


31,835 


23-00 


529 


12,167 


25-50 


650 


16,581 


2800 


784 


21.052 


23-05 


531 


12,247 


25-55 


653 


16,670 


2805 


787 


33.070 


2310 


534 


12,326 


25-80 


855 


16,777 


28-10 


790 


32,188 


2315 


536 


12,407 


25-66 


658 


16.876 


28-15 


792 


23,307 


23-20 


538 


12,487 


25-70 


.860 


16,075 


28-20 


796 


22.426 


23-25 


641 


12.588 


26-75 


863 


17,074 


38-25 


798 


23.545 


23-30 


643 


12.848 


26-80 


866 


17,174 


28-30 


801 


33.665 


23-35 


546 


12,731 


25-85 


668 


17.274 


28-36 


804 


32,786 


23-40 


548 


12.813 


25-80 


671 


17.374 


28-40 


807 


22,006 


23-46 


650 


13.896 


25-05 


873 


17.476 


28-45 


809 


23.028 


23-50 


552 


12,978 


2600 


676 


17.678 


28-50 


812 


23,140 



486 



SHIPS' BOATS 



t 


2 
815 


Cnliea. 
23,271 


• 

£ 
31-05 


x 


Cabea. 


1 

s 


x 
1,126 


Cabm. 


28-55 


964 


29,935 


33-55 1 


37,764 


28-60 


818 


23,394 


31-10 


967 


30,080 


33-60 1 


1429 


37,933 


28-65 


821 


23,517 


31-15 


970 


30,226 


33-65 1 


1432 


38,103 


28-70 


824 


23,640 


31-20 


973 


30,371 


33-70 1 


1436 


38^273 


28-75 


827 


23,764 


31-25 


97T» 


30,518 


33-76 1 


1,139 


38,443 


28-80 


829 


23.888 


31-30 


980 


30,664 


33-80 1 


1442 


38,614 


28-85 


832 


24,013 


31-35 


983 


30,811 


33-85 1 


L446 


38,786 


28-90 


835 


24,138 


31-40 


986 


30,959 


33-90 1 


L449 


38,958 


28-95 


838 


24,263 


31-45 


989 


31407 


33-95 1 


1,153 • 


39,131 


29-00 


841 
844 


24,389 
24,515 


31-50 
31-55 


992 
995 


31,256 
31,405 


34-00 1 


Si8 


39,304 


29-05 


34-05 1 


39,478 


29-10 


847 


24,642 


31-60 


999 


31,554 


34-10 1 


1463 


39,652 


29-15 


850 


24,769 


31-65 


1,002 


31,705 


34-15 1 


1,166 


39^26 


29-20 


853 


24,897 


31-70 


1,005 


31,855 


34-20 1 


1,170 


40,002 


29-25 


856 


25,025 


31-75 


1,008 


32,006 


34-25 1 


1,173 


40,177 


29-30 


858 


25,154 


31-80 


1,011 


32,157 


34-30 1 


1,176 


40,354 


29-35 


861 


25.283 


31-85 


1,014 


32,309 


34-35 1 


1480 


40,530 


29-40 


864 


25,412 


31-90 


1,018 


32,462 


34*40 1 


1,183 


40,708 


29-45 


867 


25.542 


31-95 


1,021 


32,615 


34-45 ; 1 


1487 


40385 


29-50 


870 


25,672 


32-00 


1,024 


32,768 


34-50 > 1 


1490 


41.064 


29-55 


873 


25,803 


32-05 


1,027 


32,922 


34-55 1 


14M 


4litt 


29-60 ' 


876 


25.934 


3210 


1,030 


33,076 


34-60 1 


1,197 


41,422 


29-65 


879 


26,066 


32-15 


1,034 


33,231 


34*65 1 


1,201 


41,602 


29-70 


882 


26,198 


32-20 


1,037 


33,386 


34-70 1 1 


1,204! 


41,782 


29-75 


885 


26,331 


32-25 ' 


1,040 


33,542 


34-75 1 1 


1,208 


41,968 


29-80 


888 


26.464 


32-30 1 


1,043 


33,698 


34-80 . 1 


1,211 


42,144 


29-85 


891 


26,597 


32-35 1 


1,047 


33,855 


34-85 1 


1,215 1 


42,826 


29-90 


894 


26,731 


32-40 


1,050 


34,012 


34-90 1 


1,218 


42,509 


29-95 


897 


26.865 


32-45 


1,053 


34,170 


34-95 1 


L,222 


42,692 


30-00 


900 


27,000 


32-50 


1,056 


34,328 


3500 1 


1,225 


42,875 


30-05 


903 


27,135 


32-55 1 


1,060 


34,487 


35-05 1 


U229 


43,059 


30-10 


906 


27,271 


32-60 


1,063 


34,646 


3510 1 


1,232 


43,244 


30-15 


909 


27.407 


32-65 


1,066 


34.806 


3515 1 


1,236 


43,429 


30-20 


912 


27,544 


32-70 


1,069 


34,966 


35-20 1 


1,239 


43,614 


30-25 


915 


27,681 


32-75 


1.073 


35.126 


35-25 1 


1,243 


43,800 


30-30 


918 


27,818 


32-80 


1,076 


35,288 


35-30 1 


1,246 


43,987 


30-35 


921 


27,956 


32-85 


1,079 


35,449 


35-35 1 


L,250 


44,174 


30-40 


924 


28,094 


32-90 


1.082 


35,611 


35-40 1 


1,253 


44,362 


30-45 


927 


28,233 


32-95 


1.086 


35,774 


35-45 1 


1,257 


44,550 


30-50 


930 


28.373 


33-00 


1,089 


35,937 


35-50 1 


1,260 


44,739 


30-55 


933 


28,512 


33-05 


1,092 


36,101 


35-55 1 


1,264 


44,928 


30-60 


936 


28,653 


33-10 


1,096 


36,265 


35-60 1 


1,267 


45418 


30-65 


939 


28,793 


33-15 


1,099 


36,429 


35-65 1 


1,271 


45,308 


30-70 


942 


28.934 


33-20 


1,102 


36,594 


35-70 1 


r,274 


45,499 


30-75 


946 


29,076 


33-25 


1,106 


36,760 


35-75 1 


1,278 


45,691 


30-80 


949 


29,218 


33-30 


1,109 


36,926 


35-80 1 


1,282 


45,883 


30-85 


952 


29.361 


33-35 


1,112 


37,093 


35-85 1 


1,285 


46,075 


30-90 


955 


29,504 


33-40 


1,116 


37,260 


35-90 1 


1,289 


46,268 


30-95 


958 


29,647 


33-45 


1,119 


37,427 


35-95 1 


1,292 


46,462 


31-00 


961 


29.791 


33-50 


1,122 


37,595 

1 


36-00 


1,296 


46,656 

1 



I 



r 


1 


Oabu. 


1 


I 


Cnbw. 


1 


1 


CDb«. 


36-05 


1.300 


*6.85t 


38-66 


I,«« 


57,289 


4105 


1.6SS 


S9.173 


3610 


1,303 


47.046 


38-60 


1,490 


57.512 


41-10 


1.689 


69.427 


3615 


1.307 


47.242 


38-65 


1,494 


57,736 


41-15 


1.693 


69,680 


38-20 


I.3I0 


47.438 


38-70 


1.498 


57,961 


41-20 


1,697 


69.935 


36-25 


1,314 


47.635 


38-75 


1.503 


58.186 


41-25 


1.702 


70,189 


38-30 


1.318 


47.832 


38-80 


1.505 


58,411 


41-30 


1,706 


70,4+5 


38-35 


1.331 


48,030 


38-85 


1.509 


58,637 


41-35 


1.710 


70,701 


36-40 


1.325 


48,229 


38-90 


1.513 


58.864 


41-40 


1.714 


70.958 


36-45 


1.329 


48,428 


38-95 


1,517 


59.091 


41-45 


1.718 


71.215 


36-50 


1.332 


48,627 
48.827 


39-00 
3905 


1.521 

1.525 


59.319 
59.547 


41-50 
41-55 


1.722 
1,726 


71.473 


36-65 


1,336 


71.732 


36-60 


1.3+0 


49.028 


3910 


1,529 


59.776 


41-60 


1.731 


71.991 


36' 65 


1.343 


49.229 


3915 


1,533 


60.006 


41-65 


1.735 


72,251 


38-70 


1.347 


49.431 


39-20 


1,537 


60.236 


41-70 


1.739 


72.512 


36- 7S 


1.361 


49.633 


39-25 


1.541 


60.467 


41-75 


1.743 


72.773 


36-80 


1.354 


49.836 


39-30 


1.5+4 


60.698 


41-80 


1.7+7 


73.035 


36-85 


1.358 


50,039 


39-35 


1.548 


60.930 


41-85 


1.751 


73.297 


3G-90 


1.362 


50,243 


39-40 


1.552 


81.163 


41-90 


1.758 


73.660 


36-95 


1,365 


50,448 


39-45 


1.556 


81.396 


41-95 


1,760 


73.824 


37-00 


1,389 


50.653 


39' 50 


1.560 


61.630 


42-00 


1,764 


74.088 


37-05 


1.373 


50.859 


39-55 


1,564 


61,864 


+2-05 


1.768 


74,353 


37- iO 


1,376 


51.065 


39-60 


1.568 


62.099 


42-10 


1,772 


74.818 


37-15 


1,380 


51.272 


39-85 


1.572 


62,335 


43-15 


1.777 


74.886 


37-20 


1.384 


51.479 


39-70 


1,576 


62.571 


42-20 


1,781 


75.161 


37-25 


1.388 


51.887 


39-75 


1,580 


62.807 


42-25 


1.785 


75.419 


37-30 


1.391 


51.895 


39-80 


1.584 


63.045 


42-30 


1,789 


75.687 


37-35 


1.395 


52.104 


39-35 


1.588 


63,283 


42-35 


1.794 


76.956 


37-W 


1.399 


52,314 


39-90 


1,692 


63.521 


42-40 


1.798 


76.225 


37-45 


1.403 


52,524 


39-95 


1,596 


63.760 


+2-45 


1.802 


76.495 


37-50 


1,406 


62.734 


40- 00 


1,600 


64,000 


42-50 


1.806 


76.766 


37-55 


l.*10 


52.946 


40-05 


1.604 


64.240 


42-55 


1,811 


77.037 


37-60 


1.414 


53.157 


40-10 


1.608 


64.481 


42-60 


1,815 


77.309 


37-65 


1.418 


53.370 


40- 15 


1.612 


84.723 


42' 85 


1,819 


77,681 


37-70 


1.421 


53.583 


40-20 


1.618 


84.965 


42-70 


1.823 


77,854 


37-75 


1,425 


53.796 


40-25 


1.621 


65,208 


42-75 


1.828 


78.128 


37-80 


1.429 


54.010 


40-30 


1.624 


65.451 


42-80 


1.832 


78,403 


37-85 


1,433 


54.225 


40-35 


1.628 


85.695 


42-85 


1.836 


78.678 


37-90 


1.436 


54,440 


40-40 


1,832 


65.939 


+2-90 


1.840 


78.954 


37-96 


1.4M 


54.856 


40-45 


1,836 


66.184 


42-95 


1.8+5 


79.230 


38-00 


1.444 


64,872 


40-50 


1.640 


66.430 


43-00 


1.849 


79.507 


3806 


1.448 


55,089 


40-55 


1,644 


66.676 


4305 


1.853 


79.785 


38-10 


1.452 


5.^306 


40-80 


1.84S 


86.923 


43-10 


1.858 


80.063 


3815 


1.455 


55.624 


40-65 


1.652 


67,171 


43- 15 


1.862 


80.342 


38-20 


1.459 


55.743 


40-70 


1,656 


67.419 


+3-20 


1.866 


80.622 


38-25 


1,463 


55.962 


40-75 


1.681 


67.668 


43-25 


1.871 


30.902 


38-30 


1.467 


56,182 


40-80 


1.665 


67.917 


43-30 


1.875 


81.183 


38-35 


1.471 


56.402 


40-36 


1.669 


88.187 


43-35 


1,879 


81.464 


38-40 


1,475 


56.623 


40-90 


1.673 


68.418 


43-40 


1,884 


81.747 


38-45 


1.478 


56.845 


♦0-95 


1.677 


68.669 


43-45 


1.888 


82.029 


38-80 


1.482 


57,067 


41-00 


1,681 


68,921 


43-50 


1.892 


82.313 



^4S^^^^^^^^^?bStS^^^^^^^^B 




1 


j 


i„.. 


i 1 ... 


1 


j 


.JH 




s 


« 






i< 


m 


H 




43-65 


1,897 


S2,5»T 


44-05 1,940 85,475 


4*55 


1.986 


88.418 ^H 


43- eo 


l.BO 


82,882 


4410 1,945 85,766 


44-60 


1.98S 


88,717 


43-65 


1.906 


83.167 


4415 1,949 86.058 


44-65 


1,994 


89,015 


43-70 


I.OIC 


83,453 


44^20 1,954 86.351 


44-70 


1,998 


89,315 


43-75 


1,0H 


83,740 


44-25 1,958 86,644 


44-75 


2.003 


89.615 


43-80 


1.918 


84,028 


44-30 1,962 86,938 


44-80 


2,007 


89.915 


43-85 


1.S23 


84,316 


4436 1.967 87.233 


44-85 


2,012 


90.217 


43-90 


1.927 


84.806 


41-40 1,971 87.528 


44-90 


3,016 


90.519 


43-85 


1,932 


84.894 


4445 1,976 87,824 


44-95 


2,021 


90,822 


44-00 


1,936 


85.184 


44-50 1,980 88,121 


46-00 


E,0!5 


91,125 ^^ 


(B) DECIMALS OF A FOOT FDR EACH 1-S4th OF AN INCB^^H 







1 


2 


8 


4 5 


a 


J 


8 


J, 


10 


^M 


- 


Inoh. 


loch. 


ncliH. 


lii.:lHa 


iDclio. Inchea. 

_ 


Ini'lies. 


iudiB. 


Inobe.. 


luchu 
■7600 


Inubta. 
■8333 


m 


■0000 


■0833 


■1667 


^ 


•3333-4167 


■6000 


-6833 


'6667 


A 


-0013 


-0B40 


-1680 


-2SI3 


•3340-4180 


•6013 


•6846 


'6680 


■7513 


8346 


•9180 




■0028 


-0850 


■1693 




-3369 1193 


•6026 


■6859 


■0693 


■7620 


■8359 


-9193 




■003(1 


■0872 


-1706 


■2530 


■3372 4206 


■6039 


■5872 


'6706 


•7639 


•8372 


-0206 


A 


■0052 


■08S5 


'1719 


■2552 


■3385! ^4219 


•60S2 


■5885 


■6710 


-7662 


■8386 


■9216 


<^ 


-0OB6 


■0898 


■1732 


■2565 


■3398 1 ^4232 


5066 


-68S8 


■6732 


-7666 


'8398 


■9232 


t 


■0078 


■OBll 


-1746 


•2578 


■3411 


-424Q 


■5078 


-5911 


-6745 


-7578 






a'* 


0001 


■0024 


-1758 


■2591 


■3424 


■4258 


■5091 


•6924 


-6768 


7691 


8424 


-9268 


i 


■0104 


■0937 


■1771 


■2604 


3437 


■4271 


■6104 


-6937 


■B77I 


■7604 


■8437 


■M,. - 


A 


■0117 


■0951 


•1784 


-2617 


-3451 


■4284 


■61 17 


•5951 


■0784 


7617 


-8451 


jdfl 


i 


-oiao 


■0904 


■1797 


2030 


■3464 


■4297 


■6130 


■5964 


•6797 


7630 


■8464 


-^fV 


-0143 


■0977 


■1810 


■2043 


■3477 


'4310 


■6143 


•5977 


■6810 


7643 


•8477 


il3l»H 


■OiSO 


■0090 


■1823 


■2666 


■3400 


4323 


■0156 


5990 


■6823 


7656 


•8490 


•932S 


I 


■oieit 


-1003 


'1836 


-2669 


■3603 


'4336 


-516» 


-6003 


•6836 


7669 


■8503 


-9336 


■01 BZ 


■loie 


■1849 


-2682 


■3516 


■4349 


■E182 


■6016 


■6849 


7682 


■8616 


-0349 


■0105 


■1029 


■1862 


■26B5 


3629 


■4362 


■6196 


•002B 


■68UZ 


7695 


■8529 


■»3tt_H 


i 


-0208 


-1042 


■1875 


■2708 


■3642 


■4376 


■6208 


■6012 


■6876 


7708 


■8542 


■MTtt^l 


ti 


0221 


-10S6 


■1888 


■2721 


■355G 


■4388 


-5221 


■0055 


■6888 


7721 


-8555 


.pgg^H 




-0234 


-looe 


-1901 


■2734 


■3668 


-4401 


5234 


■6068 


0901 


7734 


-3588 






■0247 


■1081 


1914 


-2747 


■3681 


■4414 


■5247 


■0081 


■6914 


7747 


■8581 


■S^^H 


A 


■02«0 


■1094 


-1927 


■2760 


3694 


■4427 


■62G0 


■0094 


6927 


7760 


•8594 




u 


■0273 


-1107 


1040 


-2773 


-3007 


■4440 


-6273 


-6107 


■0940 


7773 


•8607 


-Mtf^l 


1 


■028U 


■1120 


I9S3 


■2786 


'3620 '-4453 


■5286 


■6120 


•6953 


7786 


■8620 




i! 


■02011 


-1133 


19661 -2799 


-303.1 -4466 


5299 


■6133 


'6966 


77B9 


8833 




i 


■U!I12 


■1140 

■ 


19791 -2812 


'3H4«,-4479 


5312 


■6146 


■6979 


7812 


8646 

m 


1 













APPENDIX 










189 




Inch. 

— - 


Inch. 


iiche-. 


ndw-. 


4 


.i. 


e 1 7 

liithB».jinche«. 


Lola.. 


J... 


QdieB. IncbBj. 


i 


■0326 
■0339 
■0352 
■0385 


1159 

1172 
1185 
U38 


■1092 
■2005 
-2018 
-2031 


■2826 
■2839 
■2852 
•2865 


■36^yj 

■3672 
■3685 
■3698 


■4402 

-4505 
-4518 
■4531 


■5326 
■5339 

'5366 


■6159 
-6172 
■6185 
■6108 


0992 ; ^7826 
■7005 ■7839 
■7018 -7862 
■7031 1 -7866 


■8059 
8672 
8685 
8098 


9402 
9606 
9518 
9631 


1. 
1 


■0378 
■0391 
■0W4 
■0417 


1211 
12-24 
1237 
1250 


■2044 

■2057 
■2070 
■2083 


■2878 
-2891 
■2!»04 
■2017 


■3711 

■3724 
■3737 
■3750 


■4544 
-4557 

■4570 
■4583 


■5378 
■5391 
■5404 
■5417 


■6211 
-6224 
■6237 

■6250 


7044 
7057 
■7070 
-7083 


■7878 
■7891 
■7904 
■7917 


■8711 

■8724 
-8737 

-8760 


9644 
9557 
9570 
9583 


A 


■0*30 
-0143 

■0*50 
■0«9 


1263 

1278 
1289 
1302 


■2090 
■210!) 
2122 
■2135 


■2930 
•2943 
•2956 
■20«!l 


■3763 

■3770 
■3789 
■3802 


'4506 
■4600 
-4022 
■4(135 


■5430 
■0443 
■5456 

■5469 


■6203 
■6276 
■6289 
l63l»2 


700ti 
7100 
7122 

7136 


7930 
7043 

'7956 
7969 


■8763 
■8776 
■8780 
■8802 


9596 

9609 
9622 
9635 


il 


■W82 
■0495 

■050S 
■0521 


1315 
1328 
1341 

1354 


■2148 
■2101 


■2982 
■200.^1 

-■Jim 

■302! 


-3815 
■3828 
3841 
■3Mr>4 


■4I«8 
■4061 
■4674 

■4088 


-Ml 
'5405 
■5508 
5521 


■tl315 

-6328 
6341 
■6354 


7148 
7101 
7174 
7188 


7882 

7995 
■8008 
8021 


■8815 
■8828 
■8841 


9648 
■9661 

9674 
9688 


II 
11 


■0534 

■0547 
■0500 
■0573 


1307 
138U 
1303 
1406 


■2201 
■22U 
■2237 
■2240 


■3034 
■3047 
■3060 
■3073 


■3807 
■3880 
■3893 
■3906 


-4701 
■4714 
■4727 
■4740 


■5634 

■r«>47 

■5560 
■5573 


■0307 
0380 
■0393 
■6406 


7201 
•7214 

7227 
■7240 


■8034 

■8047 

■8073 


■8867 
■8880 
■8803 


9701 
9714 

9727 
9740 


i 


■05B6 
■0699 
■0612 

■0025 


1419 
1432 
144.-) 
1458 


■2253 

■226ti 
■2270 
■2292 


■308.. 
■3099 
'3112 
■3125 


■3919 
■3932 
■3945 
■3958 


■4753 
■4700 
■4779 
-4702 


■5580 
■3599 
■3612 
■5625 


-6419 
■6432 
■(►445 

■6458 


-7253 

-7260 
■7279 
■7292 


■8086 
•8039 
'8112 
■8126 


■8019 
8932 

8945 
■8958 


9763 

0766 
9778 
9792 


! 


■003tJ 
■0051 
■006* 
■0077 


1471 
1484 
1407 

1510 


■2305 
■23 IS 
'2331 
-2344 


■3138 
•3151 
■3164 
■3177 


■3071 

■3097 
■4010 


■4805 
■4818 
■4831 
■4844 


■5638 
■56!)1 
■560* 
-5077 


■6471 
■8*84 
■0407 
■6510 


'7306 

■7318 
7331 
'7344 


■8138 
■8151 
8164 
■8177 


■8971 
'8984 
■8907 
■9010 


9800 
9818 
9831 

9SM 


1 


■0090 
-O703 
■0716 
■0729 


1523 
1536 
15*0 
1582 


■2357 
■2370 
•2383 
-2396 


■3190 

■3203 
■3216 
-3229 


■4023 

'4036 
■4019 
■40)t2 


'4857 

■4883 
4896 


■5690 
■5703 
■5710 

■5729 


■t.523 
■0530 
■6549 
■6562 


■7357 
■7370 
■7383 

■7396 


■8190 
■8203 
-8216 

■8229 


'9023 
■0036 
-9049 
-9062 


9867 
0870 
98S3 
9890 




■0742 
■0756 

■0768 
■0781 


1576 

1589 
1602 
1615 


■2409 
-2422 
2435 

■2448 


■3242 
■3255 
■3208 

-3281 


-4076 
■4U89 
■4102 
-4115 


■4009 
-4922 
■4935 

•494H 


■5742 
■6735 

■5768 
■5781 


■6376 
■|-«i89 
■6602 
-0015 


■7409 
■7422 
■7435 

-7448 


-8Z42 
■8256 

■8268 
■8281 


■9076 
-9089 
9102 
■9115 


9000 

9922 
9936 
9948 


i 


■0704 

•0807 
-0820 


1628 
1641 
165* 

— 


2461. 
■2474 

■2487 


3294 
-3307 
-3320 


■4128 
-4141 
■4154 


■4901 
-4974 

■4087 


■5794 

■5807 
■5820 




■6628 
■0041 
■0654 


■7461 
■7474 

■7487 


■8294 
■8307 
■8320 


-9128 
'9141 

■9164 

— 1 


9961 
9974 
9987 
■0000 



SHIPS' BOATS 



(F) DECIMALS OF AN INCH FOR EACH l-64th OF AM IMC 



S£udB. 


UthB. 

I 


015625 


Fraction. 


SandJ. 


Mths. 


Dednul. 
-515625 


Frwtii 




, 




33 






2 -03125 




17 


34 


-53126 






3 -016876 






36 


■646875 




2. 


4 


0625 


\ iV 


18 


36 


-5625 


I's 




6 


078 125 






37 


-578125 




3 


6 


09375 




19 




■50375 








109375 






39 


■609375 




4 


e 


125 


i 


20 


40 


'«26 


1 




8 


140625 






41 


640625 




6 


10 


15625 

171875 




21 


42 
43 


-66620 
■671875 






12 


1875 


■A 


22 


44 


-6876 


H 




13 


203125 






45 


■703125 




7 


14 


21875 




23 


, 46 


•71876 






15 


234375 






47 


■73437S 




S 


16 
17 


25 

2*15625 


i 


24 


. 48 
1 40 


■75 
'766626 


1 


9 


18 


28125 




20 


1 50 


■78126 






19 


296876 






- fil 


■796875. 




10 


20 


3125 


A 


26 


, OS 


•8125 


ii 




21 


328125 






1 63 


■828126 






22 


34375 




27 


64 


■84376 






23 


350375 






66 


■869375 




12 


24 


375 


i 


28 


66 


■875 


I 




2S 


390626 






67' 


■690625 




13 


26 


40025 




29 


68 


■S062& 






27 


421875 






69 


■92IB75 




U 


28 


4375 




30 


60 


■9376 


H 






453126 






61 


■953125 




IS 


30 


4<i87S 




31 


62 


■96875 






31 


484375 






&3 


-934375 




16 


32 


5 


i 


32 


64 


1 


I 



(G) APPROXIMATE FREEBOARD OF CLASS I. OPEN BOA 
OF STANDARD DIMENSIONS. 

{FiiU 'lumber ofpU'oi'f nnd ,^uipmcnt on board. ( 





Fr«bo.-,rd 


Diraer'SHMu,. 


Fr««ba*rd 


t-;v 


.V 1" 


22^0' y. 7-23- X 2-75' 


1' 3i' 




r 0" 


21-0' x7^0' y 2-7' 


r 5" 




I' II" 


20-0' y. 6-75' y. 2-6" 


1' 44 




r' 10" 


19-0' y 6-.1' >: 2o' 






1' !)" 


IHV' X 6-25' >, 2-4' 




:vi.v 




17<l' y- fi*' X 2-33' 




30' 




16-0' X 573' y 2 3' 




2^9' 


r 111" 











t$ 


XV 






»» 








»♦ 








»* 








»» 








f 








• * 








•t 


n 






♦ f 








»> 


w 



»» 



INDEX 



Air-oases, baoyancy, construe lion of, 330 

for Class I a lifeboats, 21. 178 
Ib lifeboats, 22, 196 
IIa lifeboats, 201 
nested lifeboats, 268 
steel lifeboats, 340 

„ motor lifeboats, 341 
wooden motor lifeboats, 340 
method of measuring, 336 

, testing, 335 
wooden, construction of, 357 
Anchors, sea, details of, 348 
Aprons, details of, 123, 204 
.Miott's patent boat-lowering apparatus, 465 
Ash, 101 

Baboook and Wilcox, patent davits, 449 
Badges, quarter, method of fitting, 158 
Bailer, provision of, 343 
Balsa wood, 229 
Bands, stem and skeg, 155 
Barges, boata to be carried, etc., 19 
Beams, web, in Class IIa lifeboats, 207 
Beech, 100 

Benches, side, method of titting, 164 
„ stem, method of fitting, 157 
Bilge, form of, 34 

„ raih), method of fitting, 174 

„ stringers, 74 
Biscuit-cases, details of, 351 
Bit, how used, 134, 136, 154 
Blair for plank-landings, composition of. 1 43 
Bk>ck8 and falls, 414, 442 

non-toppling, Welin patent, 416 
the Bulman patent, 415 
practical rules for, 435 
Boat accommodation on vessels, requirements of the U S.A., 1 1, 20 
Boat-boilding, syllabus for instruction in, 479 
Boat-yard, the equipment of a, 105 
Boats and davits. Departmental Committee report, 61 
Boats, classification of, 20 

„ Class Ia, construction of, 1 10 

M ' ft Xb, construction of, 195 

„ „ m, cfbnstruction of, 199 

„ „ IIa, construction of, 200 

„ „ Ic, II B and lie, construction of, 223 

y, comparison between classes, 62 

t, modified Class ITa, 21 2 
• „ motor, construction of, 235 






492 INDEX 

Boats, nested, constniotion of, 266, 271 

,, for foreign -going passenger steamships, 7 
,y M „ M cargo steamships, 1 1 

M ,* »> ,» passenger sailing ships, 12 

,» „ „ „ cargo sailing ships, 12 

„ „ home trade passenger steamships, 12, 15-18 
„ „ „ „ cargo steamships, 1 4 
„ „ „ „ passenger sailing ships, 15 
„ „ „ „ cai^o sailing ships, 15 
„ repairs to, and maintenance of, 386 
„ steel, construction of, 278 
»» »» typical specification for, 284 

„ „ requirements of the U.S.A., 286. 

„ stowage and transporting, 403 
„ ,, on small coasting vessels, 419 

„ surf, construction of, 273 
Bollards, lowering, necessity for, 414, 442 

„ towing, details of, liM) 
Bottom boards. 103 
Breadths, minimum, of ojjen boats at half-midship height, 35 

„ of open boats, formula for obtaining, 35 
Breakers, water, details of, 341 
Breasthooks, details of, 1 73 
British Marine Motor Co.'s patent lifeboats, 214 
Bucket, two-gallon, provision of, 343 
Bulkheads, in Class II a lifeboats, 206 
Bulwarks, collapsible, in Class 11a lifeboats, 210 
Buoyanc}' air-cases, metal, constructitm of, 330 
,, ,, „ for Class Ia lifeboats, 21, 178 

„ „ „ ,, „ Ib hfeboats. 22. 196 

, „ Ha lifeboats, 201, 209 

,, ,, ,, „ nested lifeboats, 268 

„ „ „ ,, steel lifeboats, 340 

„ ,, ,, ,, ,, motor lifeboats, 341 

,, ,, ,, ,, wooden motor lifeboats, 340 

,, ,, ,, method of measuring, 33<i 

„ ,, ,. „ ,. testing, 335 

„ ,. ,, wooden, construction of, 3r)7 

„ centre of, 42 

,, outride, for (lass 1 h lifeboats, 196 

„ „ llAlifeboats, 202, 210 
,, reserve, for various classes of boats, 339 
Buoyant apparatus, instructions for constructing, etc., 473 

,, ,, list of ii])proved, 478 

Butts of planking, shift of, etc.. 137 

Capacity and deck area of jjontoon lifeboats, 231 

„ „ ., „ „ Class II A open lifeboats, 217 

„ of open boats. Classes I a, 1b and III, 78 
„ ,, motor boats, 340 

Capping-piece to gunwale, method of fitting, 161 
Carburetter in motor boats, nHjuirements for, 256 
Carvel-built boats, details of, 131, 149 
Caulking of plank seams, 120, 386 
C^dar, 102 

Centre of effort of sail area, 358 
„ buoyancy, 42 

,, curvature of curve of flotation, 56 
gravity, 43 






INDEX 493 

Oenire of Uteral leeistanoe, 368 

Chain-slings for motor boats, 307 

Cheek-pieoes in way of crutches, 163 

Chocks, stowage, details of, 212, 409 

Clamp used for planking, 134 

Classification of boats, 20 

Cleadingf tank, for buoyancy air-oases, 178 

Cleats, toe, method of fitting, 104 

Clinker method of planking, 131 

Coefficient of form, 33 

Conunittee, Departmental, on boats and davits, investigationB, 63 

Compass, steering, 353 

Construction of Class I a open lifeboats, 110 

Ib open lifeboats, 195 

IIa open lifeboats, 200 

III. open boats, 199 

lo, II B and lie pontoon lifeboats, 223 



»> » tf 

tf t> *> 

tf »» it 

»» »» »» 

„ „ motor boats, 235 

„ „ nested boats, 266, 271 

ft ft 

tt tt 



steel boats, 278 

surf boats, 273 
Cork, buoyancy for Class Ib open lifeboats, 196 
Corrosion in st«el lifeboats, 280 
Covering-board in Class IIa open lifeboats, 200 
Covers, boat, 354 

„ hatch, in Class IJa open lifeboats, 208 
Crane, boat-lowering. Harbinger patent, 4(^2 
Cross-piece to transom, method of construction, 129 
Crutches, method of fitting, 163 

„ number to be supplied, 347 
Curve of flotation, 55 
Curves of stability, 6(} 
Cypress, 103 

Davits number for foreign-going ])as8enger flteamships, 7 

„ cargo steamships, 11 

passenger sailing 8hix)s, 12 
cargo sailing ships, 12 
home trade passenger steamships, 12, 15-18 
„ cargo Hteamships*, 14 
,, passt'nqer sailing Hhipn, 15 
cargo sailing shi^js, 15 
steam laum^hcs, motor boats, tugs, etc., 18, 10 
„ formula) for obtaining the Hizt* of, 43(> 
„ hollow and solid, oqnivalont Hrzcs, 441 
„ round bar radial, details of, 421 
patent appliances, 444-4(^7 
Amott*s pat^'nt boat- lowering apparatus, 465 
Babcock and Wilcox pat^^nt, 449 
Graham's patent single, 455 
Harbinger boat-lowering crane, 4(J2 
Harland and WolfT'rt patent, 4(»0 
Martin ])at<?nt, 452 
McEachnie patent, 459 
Norton patent sheath-aorew, 448 
Quixo Davit and Rngineoring (!o.*b patent. 466 
Ross and AnderHon'n pat<'nt api)aratii.M, 46 1 
„ Snelling*s pat<mt boat Htowagc and launching gear, 4t»5 
„ Stewanl patent, 457 



tf »» tt »» 

>» tt tt tt ft 

»f t* t> tt *i 

ft f* tt 

ft »-.< tt ft 

it »» ft it »» 

»» »» it f» »» 

*» it t« 



»» 
»» 
t* 
»» 
tt 
»» 
• t 
t* 
tt 
ft 



♦ » »♦ 

»» »♦ »» 

>♦ '» »» 

>* »» »» 



494 INDEX 

Davits, Welin patent, 414 

„ turning-out gear, Pett's patent, 428 
„ „ „ „ Tumbull's patent, 428 

„ „ „ „ Welin's patent, 428 

Deadwoods, details of, 120, 123, 204 
Decimal conversion table, inches to feet, 40 
Decimals of a foot for each j^^th of an inch, 488 

„ „ an inch for each ^th of an inch, 490 
Deck area and capacity of pontoon lifeboats, 231 

„ „ „ „ „ Class 11a open lifeboats, 217 

Depth of open boats, formula for, 3t» 
Diagonally planked boats, 131 
Dimensions of boats, intluencc on stability, 32 

where placed, 355 
„ Class 1a, 1b and 111. open boats, 37. 38 
11a open lifeboats, 40 
1 1 B pontoon lifeboats, 40 
lie j)ontoon lifeboats, 40 
„ open boats below 125 cubic feet capacity, 39 
Dippers, water, 35 1 
Disengaging and engaging gears, 31 1 
Displacement of ships' boats, 41 
Dolly, how used, 134, 154 
Double skin boats, details of, 151 
Doubling behind ])lank 8caq)hs, 137 

,, ,, ,, knots, 126, 144. 

Drainage arrangtMuents in }>ontoon lifeboats, 233 
Drills, fire and boat, 391 
Dynamical stability, 362 

Effort, centre of, of sail areas, 358 
Elastic limit of lifting- hooks, 202 
Elm, (-aniwiian or Rock, 90 

., English, 08 

„ Wych, 98 
Emergency rations, n^quiremonts of the U.S.A., 355 
Engaging and disengaging gears, 31 1 
Engines, internal combustion, in motor boats, 255 

,. ,, Lloyd's ndes for, 262 

Equilibrium, eonditifms of, 48 

Equipment foi boats of various classes of vessels, 342-356 
motor boats, 261 
„ a 22-ft. mr)tor lifeboat, 254 
Euler's formula. 7«S 

Exemptions, provide<l in the Ti.S.A. Rules, 6 
Experiment, inclining, 70 

Falls, a])plianees for pn'venting cabling, 443 

,, method of reeving, 4 Hi 
., „ stowing, 418 
Fashion-])ieee to transom, method of fitting, 141 
Fastenings, for plank landings, details of, 138 

timber and plank, comparative methods for, 135 
Faying surface for planks, 120 
Fi'uders, roj)e, details of, 175 
Filling pieces between gunwale and shcerstrake, 159 

,, ,, to deadwoods, 120 

Fire extinguishing amvngements, 2f)0 

„ drills, etc., 391 



» ' 



INDEX 495 



»» »» 

»» »» 

f« »» 



Fish carriers, steam, boats to be carried, 19 
Floors, where fitted in Class I. o])en boats, 173 
Flotation, curve of, 55 
Foot spars and stretchers, 190 

Foreign-going passenger steamships, boats and davits for, 7 
cargo steamships, boats and davits for, 11 
passenger sailing ships, boats and davits for, 12 
cargo sailing ships, boats and davits for, 12 
Fonn, coefficient for, ('lass 1. ojM^n boats, 33 

„ of ships' boats, 28 
Formula, Euler's, 7H 

Frames of steel boats, Fawko's patent cmbossi^d, 281 
Freeboard and flomling tests, Chu«s 11 a op<'n lifeboats, 220 
„ of Class Ha open lifeboats, 217 
„ „ „ If, 11b and I Ir pontoon lifeboats, 231 
„ „ „ 1a open lifeboats, 4jK) 
Fuel tanks for motor boats, 2r)5 



(■alvanising, eleetro prrjeess, 380 

„ hot dipping process, 378 

rcas(m for, 377 
„ sheradising m«'iho(l, 379 

stwl boatH, 281 
Gangboards, in open boat^ of (*lass 1., Kif) 
Oirth measurement of ships' boats, 30 
Gouk and Nesbit's moditied Class 11 a open lifeboat, 214 
Grab lint«, method of fitting, 185 
Graham's patent single davit, 455 
Gravity, centre of, 43 
Gullet tool, where used, 130, 154 
(Gunwales, box, solid, etc., d(>tails of, 158-lt54 
for Class Ha open lifeboats, 207 
strength of, 7t 



ft 



Halyanl sheaves, metho<l of fitting, 373 

Harbinger boat-lowering crane, 4(>2 

Harland and Wolff's boat-lowering apparatus, 4(H) 

Hasps, mast, method of fitting, 372 

Hatchets, provision of, 343 

Head-sheets, 193 

" Hercules " modified Class Ha open lifeboats, 214 

Hog-piece, method of securing, 1 1 9, 205 

Home trade limits in Gn»at Hritain. 12 

„ passenger steamships, boats and davits for, 12, 15-18 
„ ,. cargo steamships, boats and davits for, 14 

passenger sailing ships, boats and davits for, 15 



»• 



„ ,. cai^^o sailing shi])s, boats and davits for, 15 
Hood-ends of planks, method of forming, 139 
Hooks, lifting, comparative tests, 298 

„ for open boats, details, 289 

„ „ „ steel boats, 283 

„ method of fitting at gangboard, 21)5, 301 

„ ., mousing arrangements, 30<) 

., ,. position of, .302 

„ „ Robinson's patent common, 300 

Hooks, lifting, strength of. 21M) 

„ „ when boat is susi)ended from near the ends, 302, 305 

„ „ „ „ „ stowed in the VVelin overfranie davit, 301 

Hoppers, steam, boats to be carried, etc., 19 



496 INDEX 

I 

Hot-bulb system for motor-boats, 258 
Hulks, boats to be carried, etc., 19 

Ignition fittings on motor, 259 

Inclining experiment, 70 

Inertia, moment of, 48 

Information, preliminary, required before construction on boats is commenced, 112 

Initial stability, etc., 50, 52 

Inspection during construction of boats, 194 

Insulation in motor boats, 256 

Internal water with a free surface, effect of, 51 

Instruction in boat-building, syllabus for, 479 

Keel -plates for lifting -hooks, deatils of, 299 
Keel, method of construction, etc., 112, 2m 
Keelson, method of construction, etc., 120 
Kingplank in Class 11a open lifeboat.s,21 1 
Knees, quarter, method of fitting, 158 
stem and stempost, 158 
thwart, method of fitting. 167 

number to be fitted, details, etc. (Tables XIV. and XVIII.) 

Ill, 170 
in steel boats, 283 



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»i »» 



Ladders, rope, provision of, 6 

I^iantcrn, oil, provision of, 344 

Larch, 101 

Launches, steam, boats to be carried, etc., 18 

Leclert's Theorem, 55 

Lever for biscuit-cases, to be supplied, 352 

life-lines, method of fitting, 185, 210 

Life -rafts, L.S.A. rules relating to, 5, 469 

Lifting -hooks, details of, 289 

lifting-sling arrangements. Class IIa open lifeboats, 209 

Lights, self- igniting, provision of, 344 

Limits for British home tra<le vessels, 12 

lx)ckers, equipment, details of, 187 

Lubzication of motors, 200 

" Lundin " patent lifeboats, 227 

Machinery for the equipment of a boat -yard, 107 

Maintenance of ships' boats. .*{86 

Manila rope, weight and strength of, 430 

Marking of ships' boats. 3r)() 

Martin patent boat transporter, 405, 408 

„ „ davits, 452 

Masts, length of, 37«) 
Mast liasp, method of fitting, 373 

„ st<»p, metliod of fitting, IS9 

,, traveller, details of, 374 
Matches in watortight tin, provision of, 344 
Mf'asiirenient of Class 1. o])en lifeboatj?, 78 

,, ,, Ha open lifeboats, 217 
„ „ ,. Fr, 11b and He pontoon lifeboats, 223 

Merchant Shipping Acts, and L.S.A. Rules, 2 
Mctaccntrc! an<l nieta<-cntric lici«:ht, 4«» 
Metarontric diagrams, 1)4 
McKatlinie's boat lowcriuir apparatus, 459 
McKay's patent safety -hook, :i<»7 



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«t ft 

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ft >» 

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tt 
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ff 



INDEX 497 

MoLean'f modified Class IIa open lifeboat, 213 
liidahip flection of various olaines of boats, 22-28 
Mills' patent engaging and disengaging gear, 316 
Moment of inertia, 48 
Motor boats, construction of, 235 
f, „ details of hull, 244 
„ „ end combinations, 247 
equipment for, 254 
installation of motor in, 255 
L.S.A. Rules for, 242 

recommendations of Departmental Committee* 242 
specification for a standard 22 ft., 250 
watertight bulkheads in, 256 
which proceed to sea, boats to be carried, etc., 18 
Mahogany, 100 
Motors, outboard, 237 

Lloyd's rules for the survey of, 262 
parafiKn, 257 

petrol or gasoline, 237, 243 
Moulds for planking boats, 130 
Mousing arrangements for lifting-hooks, 30G 

Nails, copper, particulars of, 148, 14U 
Nested boats, construction of, 266 
Norton*s patent davits, 448 

Oak, English, 07 

Oars, rowing, number and length, 347 

„ steering, length of, 347 
Oil-distributing apparatus, 348 
Oil leakage in motor boats, prevention of, 256 
" Oxylene ** non-uiflammablo wood, 93 

Pad-pieces in way of stowiige chocks, 193 
Paint, composition of, 384 
Painters, length of, 348 
Painting of ships' boats, 382 
Paraffin motors, 257 

Passenger sailing ships, foroign-goiiig, buatR and davitH for, 12 
„ „ „ home trad(i, boats and <lavits for, 15 

„ steamships, foreign-going, boats and davits for, 7 

„ „ home tnide, boats and davits for, 12, 15-18 

Pine, Oregon. 103 
„ pitch, 103 
„ red, American, 104 
„ white, 104 
„ yellow, 104 
Plane Tree, 101 
Planking, methods of, 130-154, 208 

„ strength of, 73 
Plank scarphs, 136 
PUnks, faying surface for, 1 20 
„ minimum breadth. 132 
Plugs, details of, 191 
Pontoon lifobcNftts, construction of, 223 

„ „ suitable dinieiiHionc<, 40 

Pumps, hand, 354 
Poncoei, use of, for planking, 131 
Patfcy, oompoaition of, 386 



4d8 INDEX 

V 

Quarter-badges, method of fitting, 158, 175 

„ knees, method of fitting, 158 
Quixo Davit and Engineering Co.'s boat-lowering apparatus, 466 

Rafts, life, instructions for constructing and stowing, 460 

„ „ L.S.A. Rules relating to, 5 
Rails, bilge, method of fitting, 174 
Rations, emergency, requirements of the U.S.A., 355 
Redwood, Baltic, 104 

„ Califomian, 103 

Relcasing-goars, 311 
Repairs to ships' boats, 38() 

Report of Departmental Committee on boats and davits, 61 
Reserve buoyancy for various classes of boats, 339 
Reverse gears for motors, 259 
Ridge spars, 354 
Rising, method of fitting, 154 
Riveting of steel lifeboats, 281 
Robinson's boat-releasing gears, 318 

„ patent common hooks, 307 
Roovo-»i»t, use of, for planking, 134 
Rooves for plank fastenings, etc., details of, 138, 148 
Rope, for falls, Board of Trade instructions, 442 

„ fire-clad wire, strength, weight, etc., 432 

„ manila, weight, strength, etc., 430 
Ropes, blocks, tackles, etc., practical rules for, 435 
Ross and Anderson's apparatus for lowering boats, 464 
Rot., dry and wet, 91 
Rowlocks, number to be supplied, 347 

„ method of fitting, 163 

Rubbers a$d ante-fouling arrangements, 173 
Rudder details and steering arrangements, 179 
Rules for life-saving appliances, authority for issuing, 2 

„ „ „ „ ., General Rule No. 2, 5 

♦» «« •» «• •» «« «» ,, ^"» *^ 

„ „ measurement of boats, 30, 78. 217, 223 

Sail areas, 3(>5 

,, bag, provision of, 373 
Sails, details of, 370 
,, centre of efi^ort, 35S 
,, ,. ,, lateral rcsist-aucc, 358 

,, force of wind on, 357 
,, n*guIatiouH afli^cting, 357 
„ stability and wind-preswufe curves, 363 
„ weft, warp, and salvage, 370 
Scantlings of Class 1. and 111. open boats, 111 
„ ,, ,, 11a open boats, 202 

,. 22-ft. motor boat, 250 
„ steol boat, 284 
,, ,, surf boat, 277 

Scarphs for keel, stem, and stem^wst, 114, 119 

])lank, 136 
Seats, side and lower, oi>en boats, 1(»4 
Shafts, propeller, general instructions, 261 

M ,. Lloyd's rules for, 263 

Sheaves, halyard, 373 
Sheer, inHuencc on stability, 32 



INDEX 499 



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tt t» 



Sheer, standard, open boats, 132 
Sheet cleats, 375 
Sheets, stem and head, 193 
Shrouds, method of fitting, 373 
Slings, chain, for motor boats, 307 

„ wire, for small boats, 30<i 
Snelling's patent boat-launching gear. 4((5 
Spark gaps on motor, 250 
Spars, ridge, 354 

Specification of a 22-ft. motor lifeboat, 250 
„ „ „ steel boat, 284 

„ „ „ surf boat, 277 

Spruce, 104 

Squares and cubes of numbers up to 45, 482 
Stability at large angles of inclination, 50 
„ curves, 66 

dynamical, 362 
initial, 50, 52 
levers, 47 
teste, 69, 221, 234 
Standard dimensions for open boats, 38 
Standardisation, advantages of, 30 
Steam-chest, 133 
Steel boats, construction of, 278 

hook-joint method of plating, 285 
requirements of U.S.A., 286 
Steering arrangemente, und rudders, 170 

„ grommet, 184 
Step, mast, 180 
Stem and stempoet construction, 114, 204 

„ „ skeg bands, 185 
Stem of open boate, formation of, 31 
Steward patent davite, 457 

„ disengaging gear, 326 
Stop waters, 122 

Stowage chocks. Class II a ojien lifeboats, 212 
„ „ details of, 400 

position of, 113 
of boate on small coasting sk'anier, 410 
„ ships' boate, 403 
Strakes of planking, clinker-built boatti, 132 
Strength and weight of nianiia rop(>, i'M) 

„ linrclail win* ropt*, 432 
calculaticm for open boat, 75 
of ships' boate, 72 

stability, and seating tests, (Ma.«s 11a lifcboate, 200 
Strotchnra and foot spars, lOO 
Stringers, in open boats, 74, 154, 178 

„ strength of, 74 
Surf boate, construction of, 273 
Surveys of motors, Lloyd's rules for, iJi") 
Syllabus for technical instruction in boat«building, 470 

Tackles, practical rules for, 435 
Tanks, biscuit, details of, 351 

buoyaaoy , cleading for, 1 78 

fuel, for motor boats, 258, 2()5 
Teak. 00 
Test, stabiti^^^ 



»• 

(» 

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f> »» »t 

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tt 
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»t 



600 ' INDEX 

Testing buoyancy air-cases, 335 
Teste for Class IIa open lifeboats, 218 

», f, „ Ic, IIb and lie pontoon lifeboats, 234 
Thwart knees in steel lifeboats, 283 
Thwarts, lower, in Class 11a open lifeboats, 207 

„ upper in Class 11a open lifeboats, 211 

t, number, etc., in Class I. open lifeboats, 155, 347 
Time test for lowering boats, 7 
Timber, conversion, seasoning, disecMos* etc., 84 

„ defects in, 90 

„ markings of, 96 

„ measurement of, 95 

„ non-inilammable, 93 

principal woods used, 97 
quarter sawing, etc., 88 
selecting, 94 

„ strength of, 95 
Timbers, frame, 73, 146, 207 
Toe-cloat« for crutches, 164 
Tools and machinery in boat-yard, 107 
Towing bollards, 190, 253 
Trades of vessels as affecting boats, etc., 4 
Transom, methods of construction, 127 
Transporter, Martin patent boat, 405 

„ Turubull's patent boat, 407 

Transporting arrangements for ships' boats, 402 

„ boats, Wclin system of, 407 

Traveller, mast, details of, 374 
Tugs, boats to be carried, 19 
TumbulFs turning-out gear for davits, 428 

Varnishes, when' used, and quality of, 385 
Wntilation arrangemfnts in motor boat, 2t>0 

Water breakers, details of, 351 
cooling for motors, 259 
dippers, 351 

internal, with fnH.i »urfacc, effect on stability, 51 
tjinks, galvanised iron, 351 
Wearing, method of fitting, 154 
Wt?ft and war]), in sails, 370 
Weights ot details of boat*' (^fjuipment, 391> 
„ ,, maiiila rope, 430 
„ „ materialn, 401 
,, persoiiH, 402 
„ steel rope, 432 

., wooilcn open lif«.»l)oatH, Class 1, 400 
Welin's patent davits, 444 

non- toppling blocks, 416 
stowage chocks, 411 
„ „ 8y8t<im of traversing boats, 407 

Wind pressure on sails, 301 
Win'leKy equipment of nic^or boats. 229, 23<l 
Woods, principal, used in construction of boats, 97 

Yoke-lines to rudder head, 183- 

THE END 



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FKINTKI) IX ORIIAT nBITAIN BT WIT^LTAM CLOmcs AXO 80V8. UMITXO, 




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4 



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